Synthesis of didemnolines A-D, N9-substituted β-carboline alkaloids from the marine ascidian Didemnum sp.

✍ Scribed by Robert W Schumacher; Bradley S Davidson

• Publisher: Elsevier Science
• Year: 1999
• Tongue: French
• Weight: 626 KB
• Volume: 55
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(98)01100-4

✦ Synopsis

Didenmolines A-D (1-4) were synthesized and their suuctures were confirmed through comparisons of data for the synthetic material with those obtained for natural 1-4. The synthesis of didenmolines A (1) and C (3) involved the coupling of 1-[(benzyloxy)methyl]-4-chloromethyl-5-(thiomethyl)imidazole ( 6) with 7-bromo-I~-carboline ($), while didenmolines B (2) and D (4) were formed through the analogous coupling of 6 with aorharmon (7). Intermediate 6 was efficiently ixepared from 1-[(benzyloxy)methyi]-2,4,5-tdbromoimidazole using a sequential one-pot halogen-metal exchange reaction and 7-Br-~-earboline was synthesized using a new approach.