Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Diazald | HCID 6628 | — |
| Reactant | Diazomethane | HCID 9550 | — |
| Reactant | (2S)-2-[(3S,8S,9S,10R,13S,14S,17R)-3-acetyloxy-10,13-dimethyl-2,3,4,7,8,9,11,12,14,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-17-yl]propanoic acid | HCID 99460 | — |
| Product | HCID 13475830 | HCID 13475830 | 99.4% |
Reaction Steps
An ethanolic ethereal solution of diazomethane (CH2N2), generated from N-methyl-N-nitroso-p-toluenesulfonamide (CH3C6H4SO2N(CH3)NO; Diazald), was added dropwise to a suspension of (20S)-3β-acetoxy-5-pregnene-20-carboxylic acid (10.0 g, 25.7 mmole; m.p. 228°-231° C.) in 1:9 ethanol-ether at room temperature until all the solids dissolved and pale yellow color due to an excess diazomethane persisted. Excess diazomethane was removed with a stream of N2 until the solution became colorless. Removal of solvent provided the desired methyl ester, (20S)-3β-acetoxy-5-pregnene-20-carboxylic acid methyl ester (10.3 g; Rf 0.63 on silica gel in 3:7 ethyl acetate-hexane; m.p. 140°-142° C.) in 99.4% yield. Mass spectrum, m/e (relative intensity) 402 (M+, 0), 342 (100), 327 (10), 283 (4), 255 (6), 239 (5), 234 (11 ), 221 (12), 213 (5); NMR (CDCl3) δ0.70 (s, 18--H3), 1.02 (s, 19--H3), 1.19 (d, J=6.8 Hz, 21--H3), 2.03 (s, 3--OCOCH3), 4.60 (m, 3--H), 5.37 (br d, J=4.8 Hz, 6--H).
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
|---|
| Patent number | US04512925 |
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| Source dataset | uspto-grants-1985_04 |
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| ORD ID | ord-e1661a6287114965ac7c4ce5b77c2c1f |
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| Source note | uspto-grants-1985_04 |
|---|
