Demethyl vinblastine

Figure 17 Separation of compounds using the optimum eluent composition achieved by factorial experimental design. Eluent hexane-dichloro methane-acetone-2-propanol (65 13 21 0.9, v/v) Compounds I, deacetyl-vinblastine II, vincristine III, N-demethyl-vinblastine IV, vinblastine V, deacetoxyvinblastine VI, leurosine the arrows show the unidentified peaks adjacent to vinblastine in the plant extract. (Reproduced by permission from Ref. 67.)...

Transformations of the dimeric alkaloid vinblastine (46) by Streptomyces species have been reported which involve N-demethylation (51), aromatic hydroxylation (55), and intramolecular ether formation (53). With Streptomyces albogriseolus, N-demethylation occurs in an undisclosed yield to produce 47 (51). The same organism in the hands of the same workers is also reported to lead to the formation of vinblastine ether (50) in low yield, along... 

As indicated in Table II (Section II,A) the absolute configuration of natural (+ )-vindoline (LXXXI) has been shown to be the opposite of that represented in Volume VIII, by X-ray analysis of leurocrystine methiodide (62). Leurocrystine (LCR = vincrystine), a double alkaloid formed from A, -demethyl-Aa-formylvindoline (LXXXII) and velban-amine, has been related to VLB (vincaleukoblastine = vinblastine), derived similarly frorn vindoline (LXXXI) and velbanamine (Volume VIII, and Chapter 5 this volume 3, 71, 72). The correlation of cleavamine of known absolute configuration (Section II,A) with vincaleukoblastine provides independent confirmatory evidence (70). Vindorosine (LXXXIII) has been shown, mainly by physical methods (including NMR- and ORD-data) to be demethoxyvindoline (20). Deacetylvindo-line (LXXXIV, 20a) and catharosine (deacetylvindorosine, LXXXV 18)... 

G-demethyl-2a-hydroxyhomolycorine also show DNA binding activity comparable to that of vinblastine (472). Homolycorine possesses high antiretroviral activity, accompanied by low therapeutic indices (483). Hippeastrine, in turn, displays antiviral activity against Herpes simplex type 1 (484). 

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