Patent Application
20130131182
This invention is in the field of biological medicine and specifically relates to the preparation, pharmacological activities and application of six bromophenol compounds, including
(2′-bromo-6′-(dibromomethyl)-3′,4′-dimethoxyphenyl)-(2,3-dibromo-4,5-dimet hoxyphenyl)-methanone (1),
3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(propoxymethyl)-benzyl]-benzene-1,2-diol (2),
3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(isopropoxymethyl)-benzyl]-benzene-1,2-diol (3), 3,4-dibromo-5-[2′-bromo-6′-(butoxymethyl)-3′,4′-dihydroxy-benzyl]-benzene-1,2-diol (4),
3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(isobutoxymethyl)-benzyl]-benzene-1,2-diol (5),
2,3-dibromo-1-[2′-bromo-6′-(2″-bromo-4″,5″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl]-4,5-dimethoxybenzene (6). All of the bromophenol derivatives are intended for treating type 2 diabetes mellitus as insulin sensitizers.
Type 2 diabetes mellitus (T2DM) is a chronic endocrine and metabolic disorder. To date, medications for T2DM include biguanides, sulfonylureas, α-glucosidase inhibitors and thiazolidinediones. However, there are many drawbacks in their clinical use, because that the drugs are designed for symptoms not for disease target. Consequently, more efficient and safe drugs with reasonable prices are badly needed.
Insulin resistance is the key factor of T2DM. Studies demonstrated that protein tyrosine phosphatase 1B (PTP1B) has emerged as a novel therapeutic strategy for the treatments of type 2 diabetes mellitus. PTP1B plays an important role in the negative regulation of insulin signal transduction pathways. Accumulating evidences indicated that PTP1B inhibitors increased the level of phosphorylation of the insulin receptor and its substrate, and promote glucose transporter translocation and increased glucose uptake in insulin-sensitive cells. PTP1B inhibitor played insulin analogues and insulin-sensitizing agent. Knockout the PTP1B gene or inhibition of PTP1B protein and mRNA expression with antisense oligonucleotide (ASO), not only can significantly improve the insulin sensitivity of the test mice, but also significantly reduce the risk of obesity patients. Gold-stein et al. showed that the expression of PTP1B and LAR PTP in insulin target tissues of patients with insulin resistance are increased, and the increase block the activation of the insulin receptor tyrosine and insulin signal transduction. P387L Is a missense mutation of PTP1B, Echwald et al confirmed that the gene mutation frequency was 1.4% in patients with type 2 diabetes, while only 0.5% in the control group. it is speculated that the mutation in related with type 2 diabetes. Investigation of the role of PTP1B using an antisense oligonucleotide (ASO) in ob/ob mice suggest that while PTP1B expression in liver, fat and skeletal muscle down, blood glucose of ob/ob mice returned to normal, and indicators of glucose metabolism also became normal. Additionally, insulin clamp experiments showed that the liver and peripheral tissues of diabetic mice enhanced insulin sensitivity. These results confirm the negative regulatory role of PTP1B in insulin signal transduction, and its increased activity may be a causative factor for insulin resistance and insulin receptor signaling impaired. Based on these data, PTP1B has already been considered as one of the best validated biological targets for T2DM.
Reported PTP1B inhibitors include: (1) Peptide PTP1B inhibitors, which contain mimetics of pTyr, have high affinity with PTP1B. But the compounds have poor chemical and biological stability. (2) Naphthnoquinone, inhibited PTP1B activity by modification of the active sites of PTPase. (3) Thiazolidinedione, improve blood glucose control by enhancing insulin sensitivities to the target organs. Representative compounds include ciglitazone, troglitazone and rosiglitazone. However, ciglitazone has been withdrawn from market due to severe hepatotoxicity. (4) Benzo[b]naphthol[2,3-d]furans and thiophenes, these compounds are designed based on benzbromarone (PTP1B inhibitor, IC50=26 μM) and exhibited good hypoglycemic activity in mice. Unfortunately, highly negative charged, the poor cell permeability and low bioavailability of these compounds have limited their application for the development of effective drugs. We have discovered a series of brominated marine natural products from red algae with potent PTP1B inhibition and synthesized their derivatives
(2′-bromo-6′-(dibromomethyl)-3′,4′-dimethoxyphenyl)-(2,3-dibromo-4,5-dimethoxy phenyl)-methanone (1),
3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(propoxymethyl)-benzyl]-benzene-1,2-diol (2),
3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(isopropoxymethyl)-benzyl]-benzene-1,2-diol (3), 3,4-dibromo-5-[2′-bromo-6′-(butoxymethyl)-3′,4′-dihydroxy-benzyl]-benzene-1,2-diol (4),
3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(isobutoxymethyl)-benzyl]-benzene-1,2-diol (5),
2,3-dibromo-1-[2′-bromo-6′-(2″-bromo-4″,5″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl]-4,5-dimethoxybenzene (6).
This invention provides six novel PTP1B inhibitors, which can be used for treatment of T2DM by inhibiting PTP1B and enhancing sensitivity of insulin receptor.
The structures of the six compounds are as follows:
1. (2′-bromo-6′-(dibromomethyl)-3′,4′-dimethoxyphenyl)-(2,3-dibromo-4,5-di methoxyphenyl)-methanone;
2. 3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(propoxymethyl)-benzyl]-benzene-1,2-diol;
3. 3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(isopropoxymethyl)-benzyl]-benzene-1,2-diol;
4. 3,4-dibromo-5-[2′-bromo-6′-(butoxymethyl)-3′,4′-dihydroxy-benzyl]-benzene-1,2-diol;
5. 3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(isobutoxymethyl)-benzyl]-benzene-1,2-diol;
6. 2,3-dibromo-1-[2′-bromo-6′-(2″-bromo-4″,5″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl]-4,5-dimethoxybenzene.
Scheme 1 shows the preparation of
(2′-bromo-6′-(dibromomethyl)-3′,4′-dimethoxyphenyl)-(2,3-dibromo-4,5-dimethoxy phenyl)-methanone (1).
Scheme 1 (a) bromine and compound 7 (molar ratio is 1:1), MeOH, ice bath condition; (b) Methyl iodide and compound 8 (molar ratio is 1:1˜1:1.5), K2CO3, DMF as solvent, room temperature; (c) a solution of compound 9 in diglycol (mass concentration of compound 9: 10˜15%), mass concentration 80% hydrazine hydrate solution, KOH, 110˜120° C.; (d) bromine and compound 9 (molar ratio is 2:1˜3:1), acetic acid, 60˜70° C.; (e) KMnO4, water, 90° C.; (f) Trifluoroacetic anhydride, H3PO4, 0˜60° C.; (g) N-Bromosuccinimide, AIBN, CCl4, hυ.
Synthesis and Characterization of 5-Bromo-Vanilline (8)
Under ice bath condition, to a solution of vanilline in MeOH (mass ratio, vanilline: MeOH=1:6˜1:7) was added dropwise bromine (mole ratio, vanilline: bromine=1:1) within 1-2 hours. The mixture was warmed to room temperature and stirred for further 0.5-1 hour. The mixture was cooled to 0° C. and added ice water (volume ratio, H2O:MeOH=1:2˜1:3) within 20-30 min, then precipitate was separated out. The mixture was stirred for further 15-30 min. The precipitate was filtered and washed with ice water and dried to give white solid. Spectrum analysis verified the compound is 5-Br-vanillin.
The physical and chemical properties of 5-Br-vanillin:m.p. 160-162° C. 1H-NMR (500 MHz, CDCl3) δ: 9.78 (s, 1H), 7.64 (d, J=1.65 Hz, 1H), 7.36 (d, J=1.65 Hz, 2H), 3.98 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 189.5 (CHO), 148.9 (C), 147.7 (C), 130.1, 130.0 (C), 108.2 (C), 108.1 (CH), 56.6 (CH3).
Synthesis and Characterization of 5-bromo-Veratraldehyde (9)
To a suspension of 5-Br-vanillin and K2CO3 in DMF (mass ratio, K2CO3: DMF=1:8˜1:12) was added dropwise CH3I (mole ratio, 5-Br-vanillin:CH3I=1: 1˜1:1.5) at room temperature. After stirring for 24 h, brine (18-22%) was added to quench the reaction. The mixture was extracted with tent-butyl methyl ether three times. The organic layer was collected, washed with brine (18-22%), dried over anhydrous Na2SO4 and concentrated in vacuo to give white solid. Spectrum analysis verified the compound is 5-bromo-veratraldehyde.
The physical and chemical properties: m.p. 60-62° C. 1H-NMR (500 MHz, CDCl3) δ: 9.84 (s, 1H), 7.64 (s, 1H), 7.38 (s, 1H), 3.94 (s, 3H), 3.93 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 189.7 (CHO), 154.2 (C), 151.8 (C), 133.1 (C), 128.7 (CH), 117.9 (CH), 110.2 (C), 60.8 (CH3), 56.2 (CH3).
Synthesis and Characterization of 5-bromo-3,4-dimethoxy-methylbenzene (10)
To a solution of 5-bromo-veratraldehyde in diglycol was added 80% hydrazine hydrate (mole ratio, 3-bromo-4,5-dimethoxybenzaldehyde:hydrazine hydrate=1:1˜1:1.5) at room temperature. TLC was used to monitor the reaction. Then KOH (8-12%) was added. The mixture was heated to 110-120° C. and stirred for 2-3 hours. After cooling, the resulting mixture was poured into water, and extracted with CH2Cl2 for three times. The organic lay was collected, washed with 1 mol/L HCl, dried over anhydrous MgSO4 and concentrated in vacuo to give colorless oil. Spectrum analysis verified the compound is 5-bromo-3,4-dimethoxy-methylbenzene.
The physical and chemical properties:1H-NMR (500 MHz, CDCl3) δ: 6.94 (s, 1H), 6.65 (s, 1H), 3.84 (s, 3H), 3.82 (s, 3H), 2.28 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 153.3 (C), 144.1 (C), 135.1 (C), 124.8 (CH), 117.1 (C), 112.5 (CH), 60.4 (CH3), 55.9 (CH3), 21.0 (CH3).
Synthesis and Characterization of 5,6-dibromo-veratraldehyde (11)
At room temperature, to a solution of 3-bromo-4,5-dimethoxybenzaldehyde in AcOH (mass concentration: 10-15%) was added dropwise bromine (mole ratio, bromine:3-bromo-4,5-dimethoxybenzaldehyde=2:1˜3:1) and catalyst iron powder. The mixture was heated at 60-70° C. and stirred for 4-6 hours. After cooling to room temperature, the iron powder was filtered and the filtrate was removed in vacuo. The residue was redissolved in CHCl3, and washed with 5% Na2SO3 for two times. The organic lay was collected, and concentrated in vacuo. The residue was recrystallized in acetone to give white needle crystal. Spectrum analysis verified the compound is 5,6-dibromo-veratraldehyde.
The physical and chemical properties: m.p. 128-130° C. 1H-NMR (500 MHz, CDCl3) δ: 10.27 (s, 1H), 7.48 (s, 1H), 3.94 (s, 3H), 3.92 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 191.5 (CHO), 152.8 (C), 131.0 (C), 122.8 (C), 121.9 (C), 111.7 (CH), 60.8 (CH3), 56.3 (CH3).
Synthesis and Characterization of 5,6-dibromo-veratric Acid (12)
NaHCO3, 5,6-dibromo-veratraldehyde and H2O were successively placed in a three-necked round bottom flask. The suspension was heated to 90° C. and added KMnO4 (mole ratio, KMnO4: 2,3-dibromo-4,5-dimethoxybenzaldehyde=1:1˜1:1.5) in three portions. TLC was used to monitor the reaction. The MnO2 was filtered and the filtrate was acidified. The white precipitate was filtered and dried to give white solid. Spectrum analysis verified the compound is 5,6-dibromo-veratric acid.
The physical and chemical properties: m.p. 180-181° C.; 1H NMR (500 MHz, CD3OCD3): δ 7.39 (s, 1H, H-2), 3.90 (s, 3H, H-8), 3.87 (s, 3H, H-9); 13C NMR (125 MHz, CD3OCD3): δ 169.2 (C-7), 153.6 (C-4), 150.9 (C-3), 132.8 (C-1), 127.5 (C-6), 123.8 (C-5), 114.5 (C-2), 60.9 (C-8), 56.9 (C-9).
Synthesis and characterization of
(2-bromo-3,4-dimethoxy-6-methylphenyl)-(2,3-dibromo-4,5-dimethoxyphenyl)-methanone (13)
Under ice bath condition, 5,6-dibromo-veratric acid was placed in a three-necked round bottom flask and dissolved in TFAA. To the stirred solution was added 85% H3PO4 and 1-bromo-2,3-dimethoxy-5-methylbenzene (mole ratio, 2,3-dibromo-4,5-dimethoxybenzoic acid: 1-bromo-2,3-dimethoxy-5-methylbenzene=1:1). The mixture was heated to 60° C. and TLC was used to monitor the reaction. The mixture was poured into crushed ice and extracted with CHCl3 for three times. The organic layer was collected and concentrated in vacuo. The residue was recrystallized in EtOH to give white crystal. Spectrum analysis verified the compound is (2-bromo-3,4-dimethoxy-6-methylphenyl)-(2,3-dibromo-4,5-dimethoxyphenyl)-methanone.
The physical and chemical properties: m.p. 86-88° C.; 1H NMR (500 MHz, CDCl3): δ 7.16 (s, 1H, H-6), 6.74 (s, 1H, H-5′), 3.91 (s, 3H, H-9), 3.90 (s, 3H, H-11), 3.81 (s, 3H, H-10), 3.79 (s, 3H, H-12), 2.22 (s, 3H, H-8); 13C NMR (125 MHz, CDCl3): δ 194.2 (C-7), 154.0 (C-4), 152.0 (C-4′), 150.8 (C-5), 144.6 (C-3′), 135.7 (C-1), 133.7 (C-1′), 133.0 (C-6′), 124.3 (C-2), 116.3 (C-2′), 115.5 (C-3), 115.1 (C-6), 113.8 (C-5′), 60.6 (C-9,11), 56.3 (C-10), 56.0 (C-12), 20.2 (C-8).
Synthesis and characterization of
(2-bromo-6-(dibromomethyl)-3,4-dimethoxyphenyl)-(2,3-dibromo-4,5-dimethoxyphenyl)-methanone (1)
(2-bromo-3,4-dimethoxy-6-methylphenyl)-(2,3-dibromo-4,5-dimethoxyphenyl)-methanon e and catalyst AIBN was placed in a three-necked round bottom flask, and dissolved in CCl4. Under hυ condition, to the solution was added NBS with stirring. TLC was used to monitor the reaction. The precipitate was filtered off and the filtrate was removed in vacuo to produce a brownish residue. The residue was purified by chromatography to give white solid. Spectrum analysis verified the compound is (2-bromo-6-(dibromomethyl)-3,4-dimethoxyphenyl)-(2,3-dibromo-4,5-dimethoxyphenyl)-methanone.
The physical and chemical properties: m.p. 166-169° C.; 1H NMR (500 MHz, CDCl3): δ 7.58 (s, 1H), 7.07 (s, 1H), 6.66 (s, 1H), 4.03 (s, 3H), 3.93 (s, 3H), 3.87 (s, 3H), 3.78 (s, 3H); 13C NMR (125 MHz, CDCl3): δ192.8 (CO), 155.1, 152.0, 151.2, 147.6, 137.4, 135.2, 129.2, 124.7, 116.8, 115.1, 114.4, 113.5, 60.8 (2×CH3), 56.4 (2×CH3), 36.7 (CHBr2); HRMS: [M+H]+ calcd for C18H16O5Br5: 706.6915, found: 706.6882.
Scheme 2 shows the preparation of
3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(propoxymethyl)-benzyl]-benzene-1,2-diol (2),
3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(isopropoxymethyl)-benzyl]-benzene-1,2-diol
(3), 3,4-dibromo-5-[2′-bromo-6′-(butoxymethyl)-3′,4′-dihydroxy-benzyl]-benzene-1,2-diol (4),
3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(isobutoxymethyl)-benzyl]-benzene-1,2-diol (5)
Scheme 2 (h) NaBH4, MeOH, 0° C.; (i) AlCl3, CH2Cl2, 0° C.; (j) N-Bromosuccinimide, CCl4, hυ; H2O, dioxane, reflux; (k) BBr3, CH2Cl2, 0° C.; H3PO4, corresponding alcohol, 70˜80° C.
Synthesis and Characterization of 5,6-dibromo-3,4-dimethoxy-phenyl-methanol
Under ice bath condition, to a stirred solution of 5,6-dibromo-veratraldehyde in MeOH was added NaBH4 (mole ratio, NaBH4: 5,6-dibromo-veratraldehyde=1:4˜1:3). TLC was used to monitor the reaction. 10% HCl was added into the reaction to acidified pH=5-6. MeOH was evaporated and the residue was extracted with CH2Cl2. The organic lay was collected, dried over anhydrous MgSO4 and concentrated in vacuo to give white solid. Spectrum analysis verified the compound is 5,6-dibromo-3,4-dimethoxy-phenyl-methanol.
The physical and chemical properties: m.p. 91-93° C. 1H-NMR (500 MHz, CDCl3) δ: 7.01 (s, 1H), 4.71 (s, 2H), 3.88 (s, 3H), 3.84 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 152.7 (C), 146.8 (C), 137.3 (C), 121.7 (C), 114.9 (C), 111.5 (CH), 65.9 (CH2), 60.5 (CH3), 56.2 (CH3).
Synthesis and characterization of 2,3-dibromo-1-(2′-bromo-3′,4′-dimethoxy-6′-methylbenzyl)-4,5-dimethoxy benzene (15)
Under ice bath condition, to a stirred solution of 5-bromo-3,4-dimethoxy-methylbenzene and 5,6-dibromo-3,4-dimethoxy-phenyl-methanol in CH2Cl2 was added AlCl3 (mole ratio, AlCl3:1-bromo-2,3-dimethoxy-5-methylbenzene:2,3-dibromo-4,5-dimethoxy-phenyl-methanol=1:1:1) in three portions. TLC was used to monitor the reaction. The mixture was poured into ice water. The organic layer was washed with 3% HCl three times, dried over anhydrous MgSO4 and concentrated in vacuo. The residue was recrystallized from MeOH to give white solid. Spectrum analysis verified the compound is 2,3-dibromo-1-(2′-bromo-3′,4′-dimethoxy-6′-methylbenzyl)-4,5-dimethoxy benzene
The physical and chemical properties: m.p. 114-117° C. 1H-NMR (500 MHz, CDCl3) δ: 6.76 (s, 1H), 6.15 (s, 1H), 4.19 (s, 2H), 3.89 (s, 3H), 3.84 (s, 3H), 3.81 (s, 3H), 3.56 (s, 3H), 2.17 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 152.5 (C), 152.0 (C), 146.1 (C), 144.9 (C), 135.8 (C), 134.3 (C), 129.6 (C), 122.1 (C), 121.7 (C), 117.6 (C), 113.8 (CH), 111.7 (CH), 60.4 (2×CH3), 56.1 (CH3), 56.0 (CH3), 40.5 (CH2), 20.6 (CH3).
Synthesis and characterization of (3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol (16)
Under hυ condition, to a solution of catalyst AIBN or BPO and 2,3-dibromo-1-(2′-bromo-3′,4′-dimethoxy-6′-methylbenzyl)-4,5-dimethoxy benzene and in CCl4 (mass concentration 5˜10%) was added NBS (mole ratio, AIBN or BPO: 2,3-dibromo-1-(2′-bromo-3′,4′-dimethoxy-6′-methylbenzyl)-4,5-dimethoxy benzene =1:100, NBS: 2,3-dibromo-1-(2′-bromo-3′,4′-dimethoxy-6′-methylbenzyl)-4,5-dimethoxy benzene=1.1:1) with stirring. TLC was used to monitor the reaction. Then hυ stopped. The precipitate was filtered off and the solvent was removed in vacuo to produce a brownish residue. The residue was purified by chromatography eluted with petroleum ether and ethyl acetate (8:1) to give white solid. The white solid (mass concentration 5˜10%) and K2CO3 (mass concentration 5˜10%) were dissolved in mixture of dixoane and H2O (volume ratio, 1:1) and the reaction was heated to 90-100° C. TLC was used to monitor the reaction. The mixture was extracted with CHCl3. The organic lay was collected and concentrated in vacuo to give white solid. Spectrum analysis verified the compound is (3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol.
The physical and chemical properties: m.p. 164-166° C. 1H-NMR (500 MHz, CDCl3) δ: 7.09 (s, 1H), 6.14 (s, 1H), 4.52 (s, 2H), 4.22 (s, 2H), 3.91 (s, 3H), 3.86 (s, 3H), 3.79 (s, 3H), 3.55 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 152.4 (2×C), 146.1 (C), 145.9 (C), 136.6 (C), 135.8 (C), 128.7 (C), 122.5 (C), 121.7 (C), 117.4 (C), 111.8 (CH), 111.4 (CH), 63.0 (CH2), 60.4 (2×CH3), 56.0 (2XCH3), 39.2 (CH2).
Synthesis and characterization of
3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(propoxymethyl)benzyl)benzene-1,2-diol (2)
Under 0° C. condition, to a solution of (3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol in CH2Cl2 was added dropwise BBr3 (1 mol·L−1 in CH2Cl2, mass ratio, BBr3 : compound 8=6:1˜8:1). The reaction mixture stirred over night at room temperature. Then the mixture was poured into ice-cold water and extracted with EtOAc for three times. The organic lay was collected, and concentrated in vacuo. The residue was dissolved in n-propanol and added 1˜5 mL 85% H3PO4. After refluxing for 10-12 hours, the solvent was removed in vacuo. The residue was purified by column chromatography eluted with petroleum ether and ethyl acetate (8:1) to produce yellow solid. Spectrum analysis verified the compound is 3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(propoxymethyl)benzyl)benzene-1,2-diol. The physical and chemical properties: 1H NMR (500 MHz, DMSO-d6): δ 9.75 (s, 1H), 9.69 (s, 1H), 9.27 (s, 1H), 9.14 (s, 1H), 6.88 (s, 1H), 6.05 (s, 1H), 4.17 (s, 2H), 3.99 (s, 2H), 3.26 (t, J=6.52, 2H), 1.14 (m, J=, 2H), 0.79 (t, J=7.36, 3H); 13C NMR (125 MHz, DMSO-d6): δ 144.9 (C), 144.3 (C), 142.5 (2×C), 130.5 (C), 129.0 (C), 127.5 (C), 115.4, 114.6 (C), 114.3, 113.9 (C), 112.9 (C), 71.2 (CH2), 70.3 (CH2), 38.3 (CH2), 22.2 (CH2), 10.4 (CH3); EIMS m/z 544/542/540/538[M]+ (1/3/3/1), 484/482/480/478 (2/7/7/2), 467/465/463/461 (2/6/6/2), 403/401/399 (7/15/7), 322/320 (19/18), 82/80 (42/43), 59 (100); HRMS: [M-HT]−calcd for C17H16O579Br3:536.8548; found: 536.8570.
Synthesis and characterization of
3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(isopropoxymethyl)benzyl)benzene-1,2-diol (3)
Under 0° C. condition, to a solution of (3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol in CH2Cl2 was added dropwise BBr3 (1 mol·L−1 in CH2Cl2, mass ratio, BBr3:compound 8=6:1˜8:1). The reaction mixture stirred over night at room temperature. Then the mixture was poured into ice-cold water and extracted with EtOAc for three times. The organic lay was collected, and concentrated in vacuo. The residue was dissolved in iso-propanol and added 1˜5 mL 85% H3PO4. After refluxing for 10-12 hours, the solvent was removed in vacuo. The residue was purified by column chromatography eluted with petroleum ether and ethyl acetate (8:1) to produce yellow solid. Spectrum analysis verified the compound is 3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(isopropoxymethyl)benzyl)benzene-1,2-diol.
The physical and chemical properties: 1H NMR (500 MHz, DMSO-d6): δ 9.72 (s, 1H), 9.69(s, 1H), 9.26 (s, 1H), 9.11 (s, 1H), 6.88 (s, 1H), 6.05 (s, 1H), 4.15 (s, 2H), 3.98 (s, 2H), 3.51 (m, J=6.43, 2H), 1.02 (d, J=6.43, 6H); 13C NMR (125 MHz, DMSO-d6): δ 144.9 (C), 144.3 (C), 142.5 (C), 142.4 (C), 130.5 (C), 129.3 (C), 127.5 (C), 115.4 (CH), 114.5 (C), 114.3 (C), 113.9 (CH), 112.9 (C), 79.1 (CH), 67.6 (CH2), 38.3 (CH2), 21.7 (2×CH3); EIMS m/z 544/542/540/538[M]+ (1/3/3/1), 484/482/480/478 (2/7/7/2), 467/465/463/461 (2/6/6/2), 403/401/399 (5/10/5), 322/320 (10/9), 82/80 (98/100), 59 (30); HRMS: [M-H]− calcd for C17H16O579Br3: 536.8548; found: 536.8525.
Synthesis and characterization of
3,4-dibromo-5-(2-bromo-6-(butoxymethyl)-3,4-dihydroxybenzyl)benzene-1,2-diol (4)
Under 0° C. condition, to a solution of (3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol in CH2Cl2 was added dropwise BBr3 (1 mol·L−1 in CH2Cl2, mass ratio, BBr3:compound 8=6:1˜8:1). The reaction mixture stirred over night at room temperature. Then the mixture was poured into ice-cold water and extracted with EtOAc for three times. The organic lay was collected, and concentrated in vacuo. The residue was dissolved in n-butyl alcohol and added 1˜5 mL 85% H3PO4. After refluxing for 10-12 hours, the solvent was removed in vacuo. The residue was purified by column chromatography eluted with petroleum ether and ethyl acetate (8:1) to produce yellow solid. Spectrum analysis verified the compound is 3,4-dibromo-5-(2-bromo-6-(butoxymethyl)-3,4-dihydroxybenzyl)benzene-1,2-diol.
The physical and chemical properties: 1H NMR (500 MHz, DMSO-d6): δ 9.75 (s, 1H), 9.69 (s, 1H), 9.27 (s, 1H), 9.15 (s, 1H), 6.87 (s, 1H), 6.04 (s, 1H), 4.16 (s, 2H), 3.98 (s, 2H), 3.29 (t, J=6.44, 2H), 1.36 (m, 2H), 1.22 (m, 2H), 0.80 (t, J=7.35, 3H); 13C NMR (125 MHz, DMSO-d6): δ 144.9 (C), 144.2 (C), 142.5 (2×C), 130.5 (C), 129.0 (C), 127.5 (C), 115.4 (CH), 114.6 (C), 114.3 (CH), 113.9 (C), 112.9 (C), 70.4 (CH2), 69.2 (CH2), 38.3 (CH2), 31.1 (CH2), 18.7 (CH2), 13.6 (CH3); EIMS m/z 484/482/480/478 (2/7/7/2), 467/465/463/461 (2/6/6/2), 403/401/399 (5/10/5), 322/320 (13/12), 82/80 (18/18), 59 (100); HRMS: [M-H]− calcd for C18H18O579Br3: 550.8704; found: 550.8688.
Synthesis and characterization of
3,4-dibromo-5-bromo-3,4-dihydroxy-6-(isobutoxymethyl)benzyl)benzene-1,2-diol (5)
Under 0° C. condition, to a solution of (3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol in CH2Cl2 was added dropwise BBr3 (1 mol·L−1 in CH2Cl2, mass ratio, BBr3:compound 8=6:1˜8:1). The reaction mixture stirred over night at room temperature. Then the mixture was poured into ice-cold water and extracted with EtOAc for three times. The organic lay was collected, and concentrated in vacuo. The residue was dissolved in isobutanol and added 1˜5 mL 85% H3PO4. After refluxing for 10-12 hours, the solvent was removed in vacuo. The residue was purified by column chromatography eluted with petroleum ether and ethyl acetate (8:1) to produce yellow solid. Spectrum analysis verified the compound is 3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(isobutoxymethyl)benzyl)benzene-1,2-diol.
The physical and chemical properties: 1H NMR (500 MHz, DMSO-d6): δ 9.75 (s, 1H), 9.69 (s, 1H), 9.27 (s, 1H), 9.15 (s, 1H), 6.88 (s, 1H), 6.04 (s, 1H), 4.16 (s, 2H), 3.98 (s, 2H), 3.08 (d, J=6.48, 2H), 1.68 (m, 1H), 0.78 (d, J=6.68, 6H); 13C NMR (125 MHz, DMSO-d6): δ 144.9 (C), 144.2 (C), 142.5 (2×C), 130.5 (C), 129.0 (C), 127.5 (C), 115.4 (CH), 114.6 (C), 114.3 (CH), 113.9 (C), 113.0 (C), 76.4 (CH2), 70.6 (CH2), 38.3 (CH2), 27.8 (CH), 19.1 (2×CH3); EIMS m/z 558/556/554/552 [M]+ (1/3/3/1), 484/482/480/478 (5/15/14/5), 467/465/463/461 (3/9/10/3), 404/402/400 (5/10/7), 403/401/399 (10/21/10), 322/320 (27/25), 82/80 (99/100), 57 (40); HRMS: [M-H]− calcd for C18H18O579Br3: 550.8704; found: 550.8688.
Scheme 3 shows the preparation of
2,3-dibromo-1-(2′-bromo-6′-(2″-bromo-4″,5″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl)-4,5-dimethoxybenzene (6).
Schceme 3 (1) AlCl3, CH2Cl2, room temperature; (m) Bromine, CH2Cl2.
Synthesis and characterization of
2,3-dibromo-1-(2′-bromo-6′-(3″,4″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl)-4,5-dimethoxybenzene (17)
Under ice bath condition, to a solution of veratrole (mass concentration 5˜10%) and
(3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol (mass concentration 5˜10%) in CH2Cl2 was added AlCl3 (mole ratio, AlCl3:veratrole:(3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-imethoxyphenyl)-methanol=1.2:1:1) with stirring. TLC was used to monitor the reaction. The mixture was poured into ice-water. The organic phase was washed with 3% HCl for three times, then dried over anhydrous MgSO4 and concentrated in vacuo. The residue was recrystallized from MeOH to give white solid. Spectrum analysis verified the compound is 2,3-dibromo-1-(2′-bromo-6′-(3″,4″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl)-4,5-dimethoxybenzene.
The physical and chemical properties: m.p. 138-139° C. 1H-NMR (500 MHz, DMSO-d6)δ: 6.78 (s, 1H), 6.66 (d, J=8.06 Hz, 1H), 6.50 (d, J=8.06 Hz, 1H), 6.49 (s, 1H), 5.99 (s, 1H), 4.18 (s, 2H), 3.88 (s, 3H), 3.87 (s, 3H), 3.79 (s, 3H), 3.78 (s, 3 H), 3.75 (s, 3H), 3.51 (s, 3H); 13C-NMR (125 MHz, DMSO-d6)δ: 152.1, 148.8, 147.4, 145.9, 145.3, 137.3, 135.7, 131.9, 129.7, 122.8, 121.3, 120.5, 117.2, 114.1, 112.1, 112.0, 111.2, 60.4, 60.3, 56.0, 55.9, 55.8, 55.7, 40.3, 39.8.
Synthesis and characterization of
2,3-dibromo-1-(2′-bromo-6′-(2″-bromo-4″,5″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl)-4,5-dimethoxybenzene (6)
At room temperature, to a solution of 2,3-dibromo-1-(2′-bromo-6′-(3″,4″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl)-4,5-dimethoxybenzene in CH2Cl2 was added dropwise bromine (mole ratio, bromine:2,3-dibromo-1-(2′-bromo-6′-(3″,4″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl)-4,5-dimethoxybenzene=2:1). TLC was used to monitor the reaction. The solvent was evaporated and the residue was redissolved in CHCl3. The organic phase was washed with 5% Na2SO3 for two times, and concentrated in vacuo. The residue was recrystallized in methanol to give white solid. Spectrum analysis verified the compound is 2,3-dibromo-1-(2′-bromo-6′-(2″-bromo-4″,5″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl)-4,5-dimethoxybenzene.
The physical and chemical properties: m.p. 151-152° C. 1H-NMR (500 MHz, DMSO-d6)δ: 6.97 (s, 1H), 6.56 (s, 1H), 6.41 (s, 1H), 6.16 (s, 1H), 4.23 (s, 1H), 3.86 (s, 3H), 3.83 (s, 3H), 3.80 (s, 3H), 3.76 (s, 3H), 3.70 (s, 3H), 3.57 (s, 3H); 13C-NMR (125 MHz, DMSO-d6)δ: 152.2, 152.1, 148.5, 146.0, 146.0, 145.3, 135.9, 135.5, 130.5, 129.6, 122.6, 121.6, 117.6, 115.7, 114.9, 113.7, 113.5, 112.0, 60.5, 60.4, 56.1, 56.1, 56.0×2, 40.3, 39.6.
All of the PTP1B inhibitors are compounds with PTP1B inhibitory activity. The compounds has been implicated in the negative regulation of insulin signal transduction pathways, enhanced insulin sensitivity and modulated blood glucose, and could be used for treating type 2 diabetes mellitus.
PTP1B Inhibition Assay
Construct human recombinant PTP1B engineering bacteria hGST-PTP1B-BL21 via molecular biology methods, and purify it through GST-tagged affinity chromatography. The principle is that the product pNP, which is enzymolysis of pNPP by PTP1B, absorbs at 405 nm. The activity of PTP1B inhibition can be measured by calculating the quantity of pNP.
The advantages of this invention are as follows:
The target compounds are with potent PTP1B inhibitory activities, and are promising for treatment of insulin resistance T2DM. The invention has implemented total synthesis of target compounds. The starting materials are cheap and commercial available, the procedures are simple and yields are acceptable. So the preparation of these compounds have good scale-up perspective.
Synthesis and Characterizaion of 5-bromo-vanilline (8)
To a solution of vanillin (7.6 g, 50 mmol) in MeOH (60 mL) was added dropwise Br2 (2.8 mL, 50 mmol) over a 2 h period at 0° C. The mixture was warm to room temperature for another 1 h. Then cooling to 0° C., water (25 mL) was poured over a 20 min period and resulted in the precipitation of white solid. The mixture was stirred for further 15 min. The precipitate was filtered, washed with ice water and dried to give 10.7 g of white solid. Spectrum analysis verified the compound is 5-Br-vanillin.
The physical and chemical properties: m.p. 160-162° C. 1H-NMR (500 MHz, CDCl3) δ: 9.78 (s, 1H), 7.64 (d, J=1.65 Hz, 1H), 7.36 (d, J=1.65 Hz, 2H), 3.98 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 189.5 (CHO), 148.9 (C), 147.7 (C), 130.1, 130.0 (C), 108.2 (C), 108.1 (CH), 56.6 (CH3).
Synthesis and Characterization of 5-bromo-veratraldehyde (9)
At room temperature, to a suspension of 5-Br-vanillin (4.26 g, 18 mmol) and K2CO3 (3.84 g, 24 mmol) in DMF (40 mL) was added CH3I (1.7 mL, 33 mmol) dropwise. After stirring for 24 h, 20% brine (100 mL) was added to quench the reaction. The mixture was extracted with tert-butyl methyl ether (3×100 mL). The organic layer was collected, washed with 20% brine, dried over anhydrous MgSO4 and concentrated in vacuo to give 4.2 g white solid. Spectrum analysis verified the compound is 5-bromo-veratraldehyde.
The physical and chemical properties: m.p. 60-62° C. 1H-NMR (500 MHz, CDCl3) δ: 9.84 (s, 1H), 7.64 (s, 1H), 7.38 (s, 1H), 3.94 (s, 3H), 3.93 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 189.7 (CHO), 154.2 (C), 151.8 (C), 133.1 (C), 128.7 (CH), 117.9 (CH), 110.2 (C), 60.8 (CH3), 56.2 (CH3).
Synthesis and Characterization of 5-bromo-3,4-dimethoxy-methylbenzene (10)
At room temperature, to a solution of 5-bromo-veratraldehyde (29.4 g, 120 mmol) in diglycol (200 mL) was added 80% hydrazine hydrate (13 mL). TLC was used to monitor the reation. Then 24 g KOH was added and the mixture was heated to 120° C. for 2 h. After cooling, the resulting mixture was poured into water (200 mL), and extracted with 200 mL CH2Cl2 for three times. The organic lay was collected, washed with 1 mol/L HCl (3×200 mL), dried over anhydrous Na2SO4 and concentrated in vacuo to give 24 g colorless oil. Spectrum analysis verified the compound is 5-bromo-3,4-dimethoxy-methylbenzene
The physical and chemical properties: 1H-NMR (500 MHz, CDCl3) δ: 6.94 (s, 1H), 6.65 (s, 1H), 3.84 (s, 3H), 3.82 (s, 3H), 2.28 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 153.3 (C), 144.1 (C), 135.1 (C), 124.8 (CH), 117.1 (C), 112.5 (CH), 60.4 (CH3), 55.9 (CH3), 21.0 (CH3).
Synthesis and Characterization of 5,6-dibromo-veratraldehyde (11)
At room temperature, to a solution of 5-bromo-veratraldehyde (31 g, 126 mmol) in AcOH (220 mL) was added dropwise Br2 (12.6 mL, 244 mmol) and iron powder (100 mg). The mixture was heated at 60° C. and stirred for 5 h. After cooling to room temperature, the iron powder was filtered and the filtrate was removed in vacuo. The residue was redissolved in CHCl3 (200 mL), and washed with 5% Na2SO3 (2×200 mL). The organic lay was collected, and concentrated in vacuo. The residue was recrystallized in acetone to give 27 g white needle crystal. Spectrum analysis verified the compound is 5,6-dibromo-veratraldehyde.
m.p. 128-130° C. 1H-NMR (500 MHz, CDCl3) δ: 10.27 (s, 1H), 7.48 (s, 1H), 3.94 (s, 3H), 3.92 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 191.5 (CHO), 152.8 (C), 131.0 (C), 122.8 (C), 121.9 (C), 111.7 (CH), 60.8 (CH3), 56.3 (CH3).
Synthesis and Characterization of 5,6-dibromo-veratric acid (12)
5,6-dibromo-veratraldehyde (38 g, 117 mmol) and NaHCO3(5.7 g, 80 mmol) and water (300 mL) were placed in a 500 mL three-necked round bottom flask. The suspension was heated to 90° C. and added KMnO4 (19.0 g, 100 mmol) in three portions. TLC was used to monitor the reaction and the MnO2 was filtered. The filtrate was acidified. The white precipitate was filtered and washed with water to give 36.3 g white solid. Spectrum analysis verified the compound is 5,6-dibromo-veratric acid.
The physical and chemical properties: m.p. 180-181° C.; 1H NMR (500 MHz, CD3OCD3): δ 7.39 (s, 1H, H-2), 3.90 (s, 3H, H-8), 3.87 (s, 3H, H-9); 13C NMR (125 MHz, CD3OCD3): δ 169.2 (C-7), 153.6 (C-4), 150.9 (C-3), 132.8 (C-1), 127.5 (C-6), 123.8 (C-5), 114.5 (C-2), 60.9 (C-8), 56.9 (C-9).
Synthesis and characterization of
(2-bromo-3,4-dimethoxy-6-methylphenyl)-(2,3-dibromo-4,5-dimethoxyphenyl)-methanone (13)
Under ice bath condition, to a solution of 5,6-dibromo-veratraldehyde (2.4 g, 7 mmol) in TFAA (10 mL) was added 85% H3PO4 (0.5 mL) and 5-bromo-3,4-dimethoxy-methylbenzene (1.71 g, 7.5 mmol). The mixture was heated to 60° C. TLC was used to monitor the reaction. Then the mixture was poured into crushed ice and extracted with CHCl3. The organic layer was collected dried over anhydrous MgSO4 and concentrated in vacuo. The residue was recrystallized in EtOH to give 3.5 g white crystal. Spectrum analysis verified the compound is (2-bromo-3,4-dimethoxy-6-methylphenyl)-(2,3-dibromo-4,5-dimethoxyphenyl)-methanone.
The physical and chemical properties: m.p. 86-88° C.; 1H NMR (500 MHz, CDCl3): δ7.16 (s, 1H, H-6), 6.74 (s, 1H, H-5′), 3.90 (s, 3H, H-9), 3.90 (s, 3H, H-11), 3.81 (s, 3H, H-10), 3.79 (s, 3H, H-12), 2.22 (s, 3H, H-8); 13C NMR (125 MHz, CDCl3): δ 194.2 (C-7), 154.0 (C-4), 152.0 (C-4′), 150.8 (C-5), 144.6 (C-3′), 135.7 (C-1), 133.7 (C-1′), 133.0 (C-6′), 124.3 (C-2), 116.3 (C-2′), 115.5 (C-3), 115.1 (C-6), 113.8 (C-5′), 60.6 (C-9,11), 56.3 (C-10), 56.0 (C-12), 20.2 (C-8).
Synthesis and characterization of
(2-bromo-6-(dibromomethyl)-3,4-dimethoxyphenyl)-(2,3-dibromo-4,5-dimethoxyphenyl)-methanone (1) (2-bromo-3,4-climethoxy-6-methylphenyl)-(2,3-dibmmo-4,5-dimethoxyphenyl)-methanone (4.29 g, 7.8 mmol), AIBN (43 mg) and NBS (3.45 g, 19,4 mmol) were dissolved in CCl4 (50 mL). The mixture was heated to reflux and TLC was used to monitor the reaction. Then the precipitate was filtered off and the solvent was removed in vacuo to produce a brownish residue. The residue was purified by chromatography eluted with petroleum ether and ethyl acetate (20:1) to give 1.95 g white solid. Spectrum analysis verified the compound is
(2-bromo-6-(dibromomethyl)-3,4-dimethoxyphenyl)-(2,3-dibromo-4,5-dimethoxyphenyl)-methanone
The physical and chemical properties: m.p. 166-169° C.; 1H NMR (500 MHz, CDCl3): δ 7.58 (s, 1H), 7.07 (s, 1H), 6.66 (s, 1H), 4.03 (s, 3H), 3.93 (s, 3H), 3.87 (s, 3H), 3.78 (s, 3H); 13C NMR (125 MHz, CDCl3): δ 192.8 (CO), 155.1, 152.0, 151.2, 147.6, 137.4, 135.2, 129.2, 124.7, 116.8, 115.1, 114.4, 113.5, 60.8 (2×CH3), 56.4 (2×CH3), 36.7 (CHBr2); HRMS: [M+H]+ calcd for C18H16O5Br5: 706.6915, found: 706.6882.
3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(propoxymethyl)-benzyl]-benzene-1 ,2-diol (2),
3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(isopropoxymethyl)-benzyl]-benzene-1,2-diol (3),
3,4-dibromo-5-[2′-bromo-6′-(butoxymethyl)-3′,4′-dihydroxy-benzyl]-benzene-1,2-diol (4),
3,4-dibromo-5-[2′-bromo-3′,4′-dihydroxy-6′-(isobutoxymethyl)-benzyl]-benzene-1,2-diol (5)
Synthesis and Characterization of 5,6-dibromo-3,4-dimethoxy-phenyl-methanol (14)
Under ice bath condition, to a stirred solution of 5,6-dibromo-veratraldehyde (72 g, 222 mmol) in MeOH (400 mL) was added NaBH4 (2.2 g, 5.5 mmol). TLC was used to monitor the reaction. Then 10% HCl was added to adjust the reaction to weak acidity. MeOH was evaporated and extracted with CH2Cl2. The organic lay was collected, dried over anhydrous MgSO4 and concentrated in vacuo to give 66 g white solid. Spectrum analysis verified the compound is 5,6-dibromo-3,4-dimethoxy-phenyl-methanol.
The physical and chemical properties: m.p. 91-93° C. 1H-NMR (500 MHz, CDCl3) δ: 7.01 (s, 1H), 4.71 (s, 2H), 3.88 (s, 3H), 3.84 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 152.7 (C), 146.8 (C), 137.3 (C), 121.7 (C), 114.9 (C), 111.5 (CH), 65.9 (CH2), 60.5 (CH3), 56.2 (CH3).
Synthesis and characterization of 2,3-dibromo-1-(2′-bromo-3′,4′-dimethoxy-6′-methylbenzyl)-4,5-dimethoxy benzene (15)
Under ice bath condition, to a stirred solution of 5-bromo-3,4-dimethoxy-methylbenzene (23.1 g, 100 mmol) and 5,6-dibromo-3,4-dimethoxy-phenyl-methanol (32.6 g, 100 mmol) in CH2Cl2 (300 mL) was added AlCl3 (13.4 g, 100 mmol). TLC was used to monitor the reaction. Then the mixture was poured into ice water (100 mL). The organic layer was collected and washed with 3% HCl (3×200 mL), dried over anhydrous MgSO4 and concentrated in vacuo. The residue was recrystallized from MeOH to give 48 g white solid. Spectrum analysis verified the compound is 2,3-dibromo-1-(2′-bromo-3′,4′-dimethoxy-6′-methylbenzyl)-4,5-dimethoxy benzene.
The physical and chemical properties: m.p. 114-117° C. 1H-NMR (500 MHz, CDCl3) δ: 6.76 (s, 1H), 6.15 (s, 1H), 4.19 (s, 2H), 3.89 (s, 3H), 3.84 (s, 3H), 3.81 (s, 3H), 3.56 (s, 3H), 2.17 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 152.5 (C), 152.0 (C), 146.1 (C), 144.9 (C), 135.8 (C), 134.3 (C), 129.6 (C), 122.1 (C), 121.7 (C), 117.6 (C), 113.8 (CH), 111.7 (CH), 60.4 (2×CH3), 56.1 (CH3), 56.0 (CH3), 40.5 (CH2), 20.6 (CH3).
Synthesis and characterization of
(3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol (16)
Under hυ condition, to a solution of AIBN (350 mg) and 2,3-dibromo-1-(2′-bromo-3′,4′-dimethoxy-6′-methylbenzyl)-4,5-dimethoxy benzene (35 g, 65 mmol) in CCl4 (400 mL) was added NBS (12.7 g, 71 mmol). TLC was used to monitor the reaction. The precipitate was filtered off and the solvent was removed in vacuo to produce a brownish residue. The residue was purified by chromatography eluted with petroleum ether and ethyl acetate (8:1) to give benzyl bromide as white solid. The white solid and K2CO3 (mass ratio 2:1) were dissolved in mixture of dixoane and H2O (60 mL, volume ratio 1:1) and the reaction was heated to 90° C. TLC was used to monitor the reaction. The mixture was extracted with CHCl3 (100 mL) and H2O (100 mL). The organic lay was collected and concentrated in vacuo to give 12.5 g white solid. Spectrum analysis verified the compound is (3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol.
The physical and chemical properties: m.p. 164-166° C. 1H-NMR (500 MHz, CDCl3) δ: 7.09 (s, 1H), 6.14 (s, 1H), 4.52 (s, 2H), 4.22 (s, 2H), 3.91 (s, 3H), 3.86 (s, 3H), 3.79 (s, 3H), 3.55 (s, 3H); 13C-NMR (125 MHz, CDCl3) δ: 152.4 (2×C), 146.1 (C), 145.9 (C), 136.6 (C), 135.8 (C), 128.7 (C), 122.5 (C), 121.7 (C), 117.4 (C), 111.8 (CH), 111.4 (CH), 63.0 (CH2), 60.4 (2×CH3), 56.0 (2×CH3), 39.2 (CH2).
Synthesis and characterization of
3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(propoxymethyl)benzyl)benzene-1,2-diol (2)
(3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol (0.90 g, 1 mmol) was dissolved in 20 mL CH2Cl2, then BBr3 (1 mol·L−1 in CH2Cl2, 16 mL) was added dropwise while stirring at 0° C. The reaction mixture stirred over night at room temperature. Then the solution was poured into ice water (50 mL) and extracted with EtOAc (3×50 mL). The organic lay was collected, and concentrated in vacuo. The residue was dissolved in n-propanol (15 mL) and H3PO4 (1 mL). After refluxing for 12 hours, the solvent was removed in vacuo. The residue was purified by column chromatography eluted with petroleum etherand EtOAc (1:1) to produce 0.5 g yellow solid. Spectrum analysis verified the compound is 3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(propoxymethyl)benzyl)benzene-1,2-diol
The physical and chemical properties: 1H NMR (500 MHz, DMSO-d6): δ 9.75 (s, 1H), 9.69 (s, 1H), 9.27 (s, 1H), 9.14 (s, 1H), 6.88 (s, 1H), 6.05 (s, 1H), 4.17 (s, 2H), 3.99 (s, 2H), 3.26 (t, J=6.52, 2H), 1.14 (m, J=, 2H), 0.79 (t, J=7.36, 3H); 13C NMR (125 MHz, DMSO-d6): δ 144.9 (C), 144.3 (C), 142.5 (2×C), 130.5 (C), 129.0 (C), 127.5 (C), 115.4, 114.6 (C), 114.3, 113.9 (C), 112.9 (C), 71.2 (CH2), 70.3 (CH2), 38.3 (CH2), 22.2 (CH2), 10.4 (CH3); EIMS m/z 544/542/540/538[M]+ (1/3/3/1), 484/482/480/478 (2/7/7/2), 467/465/463/461 (2/6/6/2), 403/401/399 (7/15/7), 322/320 (19/18), 82/80 (42/43), 59 (100); HRMS: [M-H]− calcd for C17H16O579Br3: 536.8548; found: 536.8570.
Synthesis and characterization of
3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(isopropoxymethyl)benzyl)benzene-1,2-diol (3) (3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol (0.90 g, 1 mmol) was dissolved in 20 mL CH2Cl2, then BBr3 (1 mol·L−1 in CH2Cl2, 16 mL) was added dropwise while stirring at 0° C. The reaction mixture stirred over night at room temperature. Then the solution was poured into ice water (50 mL) and extracted with EtOAc (3×50 mL). The organic lay was collected, and concentrated in vacuo. The residue was dissolved in iso-propanol (15 mL) and H3PO4 (1 mL). After refluxing for 12 hours, the solvent was removed in vacuo. The residue was purified by column chromatography eluted with petroleum etherand EtOAc (1:1) to produce 0.5 g yellow solid. Spectrum analysis verified the compound is 3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(isopropoxymethyl)benzyl)benzene-1,2-diol
The physical and chemical properties: 1H NMR (500 MHz, DMSO-d6): δ 9.72 (s, 1H), 9.69 (s, 1H), 9.26 (s, 1H), 9.11 (s, 1H), 6.88 (s, 1H), 6.05 (s, 1H), 4.15 (s, 2H), 3.98 (s, 2H), 3.51 (m, J=6.43, 2H), 1.02 (d, J=6.43, 6H); 13C NMR (125 MHz, DMSO-d6): δ 144.9 (C), 144.3 (C), 142.5 (C), 142.4 (C), 130.5 (C), 129.3 (C), 127.5 (C), 115.4 (CH), 114.5 (C), 114.3 (C), 113.9 (CH), 112.9 (C), 79.1 (CH), 67.6 (CH2), 38.3 (CH2), 21.7 (2×CH3); EIMS m/z 544/542/540/538[M]+ (1/3/3/1), 484/482/480/478 (2/7/7/2), 467/465/463/461 (2/6/6/2), 403/401/399 (5/10/5), 322/320 (10/9), 82/80 (98/100), 59 (30); HRMS: [M-H]− calcd for C17H16O579Br3: 536.8548; found: 536.8525.
Synthesis and characterization of
3,4-dibromo-5-(2-bromo-6-(butoxymethyl)-3,4-dihydroxybenzyl)benzene-1,2-diol (4)
(3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol (0.90 g, 1 mmol) was dissolved in 20 mL CH2Cl2, then BBr3 (1 mol·L−1 in CH2Cl2, 16 mL) was added dropwise while stirring at 0° C. The reaction mixture stirred over night at room temperature. Then the solution was poured into ice water (50 mL) and extracted with EtOAc (3×50 mL). The organic lay was collected, and concentrated in vacuo. The residue was dissolved in n-butyl alcohol (15 mL) and H3PO4 (1 mL). After refluxing for 12 hours, the solvent was removed in vacuo. The residue was purified by column chromatography eluted with petroleum etherand EtOAc (1:1) to produce 0.4 g yellow solid. Spectrum analysis verified the compound is 3,4-dibromo-5-(2-bromo-6-(butoxymethyl)-3,4-dihydroxybenzyl)benzene-1,2-diol.
The physical and chemical properties: 1H NMR (500 MHz, DMSO-d6): δ 9.75 (s, 1H), 9.69 (s, 1H), 9.27 (s, 1H), 9.15 (s, 1H), 6.87 (s, 1H), 6.04 (s, 1H), 4.16 (s, 2H), 3.98 (s, 2H), 3.29 (t, J=6.44, 2H), 1.36 (m, 2H), 1.22 (m, 2H), 0.80 (t, J=7.35, 3H); 13C NMR (125 MHz, DMSO-d6): δ 144.9 (C), 144.2 (C), 142.5 (2×C), 130.5 (C), 129.0 (C), 127.5 (C), 115.4 (CH), 114.6 (C), 114.3 (CH), 113.9 (C), 112.9 (C), 70.4 (CH2), 69.2 (CH2), 38.3 (CH2), 31.1 (CH2), 18.7 (CH2), 13.6 (CH3); EIMS m/z 484/482/480/478 (2/7/7/2), 467/465/463/461 (2/6/6/2), 403/401/399 (5/10/5), 322/320 (13/12), 82/80 (18/18), 59 (100); HRMS: [M-H]−1 calcd for C18H18O579Br3: 550.8704; found: 550.8688.
Synthesis and characterization of
3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(isobutoxymethyl)benzyl)benzene-1,2-diol (5)
(3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol (0.90 g, 1 mmol) was dissolved in 20 mL CH2Cl2, then BBr3 (1 mol·L−1 in CH2Cl2, 16 mL) was added dropwise while stirring at 0° C. The reaction mixture stirred over night at room temperature. Then the solution was poured into ice water (50 mL) and extracted with EtOAc (3×50 mL). The organic lay was collected, and concentrated in vacuo. The residue was dissolved in iso-butanol (15 mL) and H3PO4 (1 mL). After refluxing for 12 hours, the solvent was removed in vacuo. The residue was purified by column chromatography eluted with petroleum etherand EtOAc (1:1) to produce 0.35 g yellow solid. Spectrum analysis verified the compound is 3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(isobutoxymethyl)benzypbenzene-1,2-diol.
The physical and chemical properties: 1H NMR (500 MHz, DMSO-d6): δ 9.75 (s, 1H), 9.69 (s, 1H), 9.27 (s, 1H), 9.15 (s, 1H), 6.88 (s, 1H), 6.04 (s, 1H), 4.16 (s, 2H), 3.98 (s, 2H), 3.08 (d, J=6.48, 2H), 1.68 (m, 1H), 0.78 (d, J=6.68, 6H); 13C NMR (125 MHz, DMSO-d6):δ 144.9 (C), 144.2 (C), 142.5 (2×C), 130.5 (C), 129.0 (C), 127.5 (C), 115.4 (CH), 114.6 (C), 114.3 (CH), 113.9 (C), 113.0 (C), 76.4 (CH2), 70.6 (CH2), 38.3 (CH2), 27.8 (CH), 19.1 (2×CH3); EIMS m/z 558/556/554/552 [M]+ (1/3/3/1), 484/482/480/478 (5/15/14/5), 467/465/463/461 (3/9/10/3), 404/402/400 (5/10/7), 403/401/399 (10/21/10), 322/320 (27/25), 82/80 (99/100), 57 (40); HRMS: [M-H]−1 calcd for C18H18O579Br3: 550.8704; found: 550.8680.
Synthesis and characterization of
2,3-dibromo-1-(2′-bromo-6″-(3″,4″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl)-4,5-dimethoxybenzene (17)
Under ice bath condition, to a solution of veratrole (0.69 g, 5 mmol) and (3-bromo-2-(2′,3′-dibromo-4′,5′-dimethoxybenzyl)-4,5-dimethoxyphenyl)-methanol (2.78 g, 5 mmol) in CH2Cl2 was added AlCl3 (0.8 g, 7 mmol). TLC was used to monitor the reaction. The mixture was poured into ice-water. The organic phase was washed with 3% HCl for three times, then dried over anhydrous MgSO4 and concentrated in vacuo. The residue was recrystallized from MeOH to give 2.8 g white solid. Spectrum analysis verified the compound is 2,3-dibromo-1-(2′-bromo-6′-(3″,4″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl)-4,5-dimethoxybenzene.
The physical and chemical properties: m.p. 138-139° C. 1H-NMR (500 MHz, DMSO-d6)δ: 6.78(s, 1H), 6.66 (d, J=8.06 Hz, 1H), 6.50 (d, J=8.06 Hz, 1H), 6.49 (s, 1H), 5.99 (s, 1H), 4.18 (s, 2H), 3.88 (s, 3H), 3.87 (s, 3H), 3.79 (s, 3H), 3.78 (s, 3H), 3.75 (s, 3H), 3.51 (s, 3H); 13C-NMR (125 MHz, DMSO-d6)δ: 152.1, 148.8, 147.4, 145.9, 145.3, 137.3, 135.7, 131.9, 129.7, 122.8, 121.3, 120.5, 117.2, 114.1, 112.1, 112.0, 111.2, 60.4, 60.3, 56.0, 55.9, 55.8, 55.7, 40.3, 39.8.
Synthesis and characterization of
2,3-dibromo-1-(2′-bromo-6′-(2″-bromo-4″,5″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl)-4,5-dimethoxybenzene (6)
At room temperature, to a solution of
2,3-dibromo-1-(2′-bromo-6′-(3″,4″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl)-4,5-dimethoxybenzene (1 g, 1.48 mmol) in CH2C12 (20 mL) was added dropwise bromine (0.15 mL, 2.96 mmol). The reaction lasted 1-2 h. TLC was used to monitor the reaction. The solvent was evaporated and the residue was redissolved in CHCl3. The organic phase was washed with 5% Na2SO3 for two times, and concentrated in vacuo. The residue was recrystallized in MeOH to give 0.844 g white solid. Spectrum analysis verified the compound is
2,3-dibromo-1-(2′-bromo-6′-(2″-bromo-4″,5″-dimethoxybenzyl)-3′,4′-dimethoxybenzyl)-4,5-dimethoxybenzene.
The physical and chemical properties: m.p. 151-152° C. 1H-NMR (500 MHz, DMSO-d6)δ: 6.97 (s, 1H), 6.56 (s, 1H), 6.41(s, 1H), 6.16 (s, 1H), 4.23 (s, 1H), 3.86 (s, 3H), 3.83 (s, 3H), 3.80 (s, 3H), 3.76 (s, 3H), 3.70 (s, 3H), 3.57 (s, 3H); 13C-NMR (125 MHz, DMSO-d6)δ: 152.2, 152.1, 148.5, 146.0, 146.0, 145.3, 135.9, 135.5, 130.5, 129.6, 122.6, 121.6, 117.6, 115.7, 114.9, 113.7, 113.5, 112.0, 60.5, 60.4, 56.1, 56.1, 56.0×2, 40.3, 39.6.
Compounds 1, 2, 3, 4, 5 and 6 were dissolved in DMSO. 2 μL of samples were placed into the system (50 mM Tris-HCl, pH 6.5, 2 mM pNPP, 2% DMSO, 30 nM hGST-PTP1B). DMSO was distributed as negative control and Na3VO4 was positive control. The reaction was at 30° C. and monitored at 405 nm for 3 min Inhibitory rate was calculated according to the following formula:
% inhibition=100%×[(Vsample-VDMSO)/(VDMSO-VDMSO)]
The results are shown in Table 1.
The results showed that all of the compounds exhibit potent PTP1B inhibition, and are promising for treatment of T2DM.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201010248815.3 | Aug 2010 | CN | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/CN2011/076927 | 7/7/2011 | WO | 00 | 1/31/2013 |
