Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Phosphoric Acid | HCID 1004 | — |
| Reactant | Sodium Hydroxide | HCID 14798 | — |
| Reactant | Colchicoside | HCID 92763 | — |
| Solvent | Water | HCID 962 | — |
| Product | 3-Demethylcolchicine | HCID 299664 | 102.3% |
Reaction Steps
A mixture of 250 mg of colchicoside and 2 ml of 85-86% H3PO4 is stirred at 25° C. for 24 hours. The yellow solution is diluted with 10 ml of water, adjusted to pH 5 by addition of 2N NaOH and extracted with methylene chloride. The extracts are dried (Na2SO4), evaporated and chromatographed on Al2O3 (basic, Alfa Division, CH2C12 /MeOH=95:5). The appropriate fractions after evaporation of solvent and crystallization from acetone afford 180 mg (89%) of 3-demethylcolchicine: mp 176°-177° C. (resolidification at 205°-210° C. and 2nd mp 270° C. (dec.), [α]D =-151° (solvate crystal, CHCl3).
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
|---|
| Patent number | US05175342 |
|---|
| Source dataset | uspto-grants-1992_12 |
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| ORD ID | ord-ea6170817d5248558a3d751eeb199b7d |
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| Source note | uspto-grants-1992_12 |
|---|
