Renierone

Several isoquinolinequinones are natural products. From a bright-blue marine sponge of Reniera sp., renierone (260) was isolated as the major antimicrobial antimetabolite (79TL4163). Later, related quinones were isolated... 

Renierone was synthesized from 7-methoxy-6-methylisoquinoline in seven steps (81CPB595 86CPB4056) 261 and 262 were prepared by the same approach (85CPB2582 86CPB4056). In another total synthesis, in the last step, oxidative demethylation of 278 yielded a mixture of renierone (260) and the o-quinone 279 in a ratio of about 3 2 (80TL4819). 

For the cytotoxicity against mouse lymphoma cells, renierone and 1,6-dimethyl-7-methoxy-5,8-dihydroisoquinolin-5,8-dione were found to be the most active derivatives with EC50S of 1.1 p,g/mL and 1.7 ig/mL, respectively. From the results obtained, in the described bioassays, it is obvious that the antibacterial and fungicidal activity of the compounds under study is not paralleled by the insecticidal activity towards neonate... 

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. 

Kubo, A. and Nakahara, S. (1981) Synthesis of renierone antimicrobial metabolite from a marine sponge, Seniera sp. Chem. L harm. Bull., 29, 595-596. 

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