| 摘要 |
<p>(A) Prepn. of cobamide derivs. (vitamin B12 and analogues with modified molecules) having gp. R attached to Co atom by condensing fully reduced cobamide under non-oxidising conditions with approp. agent to introduce R (e.g. R halides, mesylate, tosylate etc.). R = aliphatic hydrocarbon gp. opt. substd., acyl, or alkyl-, aralkyl- or aryl-sulphonyl. (B) Products of (A), except vitamin B12 coenzyme and the co-5'-deoxyadenosyl derivs. of other cobamides with same side chains on pyrrole ring as in vitamin B12. Vitamin B12 coenzyme antagonists (when adenosine moiety of coenzyme replaced by Et, uridine or inosine gp. or isopropylidine adenosine gp.); Me deriv. is coenzyme in Me transfer to homocysteine in methionine formation.</p> |
