Reniera isoindole

Parker, K.A., Cohen, I.D., Padwa, A., and Dent, W. (1984) Cycloadditions of non-stabdized azomethine ylides and quinones. Synthesis of the Reniera isoindole. Tetrahedron Lett., 25,4917-4920. 

The synthetic viability of this protocol was demonstrated by the efficient synthesis of an isoindole alkaloid from the Mexican sponge Reniera. a-Cyanosi-lylamine (9) was treated with AgF, in the presence of dipolarophile 10 to furnish the requisite cycloadduct in 68%. An advanced intermediate in the synthesis of nicotine was also prepared by cycloaddition of 11 with phenylvinylsulfone giving the requisite adduct 12 in a 3 1 diastereomic mixture (Schem 3.3). 

A sponge belonging to the genus Reniera furnished a series of antimicrobial isoquinolines and an isoindole derivative (197), renierone (319), mimosamycin (320), N-formyl-l,2-dihydrorenierone (321), 0-de-methylrenierone (322), 1,6-dimethyl-7-methoxy-5,8-dihydroisoquino-line-5,8-dione (323), 2,5-dimethyl-6-methoxy-4,7-dihydroisoindole-4,7-dione (324), and renieramycins A-D (325-328). Mimosamycin (320) was originally isolated from Streptomyces lavendulae. Compounds 319 and 321, both inhibited cell division in the fertilized sea urchin egg assay. 

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