Claims
- 1. A process for preparation of a crystalline complex of formula I: ##STR7## wherein: R.sub.1 represents CH.sub.3 or H;
- comprising reacting a compound of formula II: ##STR8## with imidazole in the presence of a solvent to yield the compound of formula I and purification and isolation of a compound of formula I.
- 2. A process according to claim 1 wherein the solvent is selected from the group consisting of hydrocarbons selected from hexane(s), heptene(s) and pentene(s); ethers such as diethyl ether, t-butylmethylether, tetrahydrofuran; esters such as methyl acetate, ethyl acetate, propyl acetate, isopropylacetate, butyl acetate; toluene, benzene, chlororbenzene, xylene, dimethylformamide, dimethylsulfoxide, N,N-dimethylacetamide, 1-ethyl-2-pyrrolidinone, 1-methyl-2-pyrrolidinone, methylene chloride, dichloroethane, chloroform, acetone, methylethyl ketone, methanol, ethanol, propanol, isopropyl alcohol, butanol, amyl alcohol; and any combination thereof.
- 3. A process according to claim 2 wherein the solvent is isopropyl acetate, isopropyl acetate/hexane(s), isopropyl acetate/hexane(s)/toluene, or isopropyl acetate/THF.
- 4. A process according to claim 1 wherein R.sup.1 is methyl.
- 5. A process according to claim 1 wherein the mole ratio of compound II to imidazole is about 1 to about 2.
- 6. A process according to claim 5 wherein the mole ratio of compound II to imidazole is about 1 to about 1.2.
- 7. A process according to claim 1 wherein the reaction is carried out at a temperature of about about -10.degree. C. to about 40.degree. C.
- 8. A process according to claim 7 wherein the reaction is carried out at a temperature of about 0.degree. C. to about 10.degree. C.
- 9. A crystalline complex of formula I: ##STR9## wherein: R.sub.1 represents CH.sub.3 or H.
- 10. The compound of claim 7 wherein R.sub.1 represents CH.sub.3.
Parent Case Info
This application claims the benefit of U.S. provisional Application Ser. No. 60/058,215, filed Sep. 9, 1997.
Non-Patent Literature Citations (2)
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