Claims
- 1. A compound of the formula ##STR5## wherein R.sup.1 -R.sup.4, independently, are hydrogen or chlorine, R.sup.5 is --COOMe or --SO.sub.3 Me, Me is an alkali metal cation, X is sulfur or selenium, provided R.sup.5 is --SO.sub.3 Me when X is sulfur.
- 2. A compound in accordance with claim 1, o-(6-hydroxy-3-oxo-3H-thioxanthen-9-yl)-benzenesulfonic acid or its disodium salt.
- 3. A compound in accordance with claim 1, o-(6-hydroxy-3-oxo-3H-selenoxanthen-9-yl)-benzoic acid or its disodium salt.
- 4. A compound in accordance with claim 1, o-(6-hydroxy-3-oxo-3H-selenoxanthen-9-yl)-benzenesulfonic acid or its disodium salt.
Priority Claims (1)
Number |
Date |
Country |
Kind |
3637/83 |
Jul 1983 |
CHX |
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Parent Case Info
This is a division of application Ser. No. 620,418 filed June 14, 1984, now U.S. Pat. No. 4,551,214, issued 11-5-85.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
1532790 |
Weiler |
Apr 1925 |
|
2157351 |
Schneider et al. |
May 1939 |
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3539590 |
Oftedahl |
Nov 1970 |
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Foreign Referenced Citations (1)
Number |
Date |
Country |
1592170 |
Jul 1981 |
GBX |
Non-Patent Literature Citations (2)
Entry |
J.C. S. Chem. Comm. "Photolytic Production of Vitamin D, The Preparative Value of a Photo-Sensitiser", S. Eyley, D. Williams, p. 858 (1975). |
Nouveau Journal de Chimie, "Photosensitized Isomerization of Previtamin D.sub.2 and Tachysterol and the Related 1,2-Bis-(1-Cyclopentenyl) Ethylene: Torsional Potential Curves of Triene Triplets", M. Denny, R. Liu, vol. 2, No. 6, pp. 637-641. |
Divisions (1)
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Number |
Date |
Country |
Parent |
620418 |
Jun 1984 |
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