TOTAL SYNTHESIS OF (+ -)-DRAGMACIDIN - A CYTOTOXIC BIS(INDOLE)ALKALOID OF MARINE ORIGIN/

The total synthesis of the cytotoxic marine alkaloid, (+/-)-dragmacidi n, indol-3-yl)-4-methyl-2-piperazinyl]-1H-indol-4-ol, is described. Th e synthesis proceeds through the condensation of 6-bromoindol-3-yl)-al pha-(methylamino)acetonitrile with (6,7-dibromo-4-methoxyindol-3-yl)-a lpha-oxoacetyl chloride. The product of this condensation was converte d in two steps to an intermediate containing the central diketopiperaz ine ring which after reduction and deprotection gave the racemic natur al product along with its cis isomer. An efficient preparation of 6,7- dibromo-4-methoxyindole is also presented.