Preparation of 4.beta.- amino podophyllotoxin compounds
US5338867A · kind A · utility
6Cited by
5References
5Claims
0Family size
Assignee
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Key dates
| Filing date | Apr 24, 1992 |
| Grant date | Aug 16, 1994 |
| Priority date | — |
| Expiry date | Apr 24, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D493/04
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A method of preparing a 4'-0-demethy-4.beta.-NHR podophyllotoxin, where R is an aryl or dialkyl amino alkyl group, is disclosed. The method includes reacting H.sub.2 NR under basic conditions with a mixture of .alpha. and .beta. epimers of 4'-0-demethyl-4-bromo-podophyllotoxin, to form an epimeric mixture of the 4'-0-demethyl-4-NHR-podophyllotoxin compounds, removing acidic impurities which bind to silica gel in a dichloromethane solvent, and crystallizing 4'-0-demethyl-4.beta.-NHR-podophyllotoxin from its .alpha. epimer.
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