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We record the first synthesis of rocaglamide, assignment of its absolute stereochemistry, and the development of a novel oxidative cyclization to create the dihydrobenzofuran ring

Seven examples of the novel 4H-furo[3,4-b]indole ring system (3-9)-a stable, synthetic analogue of indole-2,3-quinodimethane have been synthesized in 6-8 steps from simple indoles in overall yiels of 21-28%. These 4H-furo[3,4-b]indoles undergo Diels-Alder reactions with several dienophiles (dimethyl acetylenedicarboxylate N-phenylmaleimide, benzyne), inclunding ethyl acrylate, witch reacts regiospecifically with furoindole 4 to afford a single carbazole ester (59). This result, predicted by molecular orbital calculations, was used to design and execute a regiospecific Diels-Alder synthesis of the antitumor alkaloid ellipticine (63)

A new class of guanidino prodrug is efficiently synthesized from an amine and an appropriate N,N′-bis(acyloxymethoxycarbonyl)-S-methylisothiourea. The N,N′-bis(acyloxymethoxycarbonyl)-S-methylisothiourea is readily prepared from S-methylisothiourea and the corresponding acyloxymethyl carbonochloridate in good yield. The N,N′-bis(acyloxymethyl carbamate) derivatives of the highly basic guanidino group serve as lipophilic, uncharged, esterase-activatable prodrugs of simple guanidine containing molecules.

Furoindoles 7 and 16 undergo smooth intramolecular Diels-Alder reactions to afford, after dehydration, hydrolysis, and oxidation, benzocarbazoles 11 and 21, respectively.

Generation of imino-quinone methide type intermediates from 2-aminothiazole-5-carbinols using alkylsulfonic acids in nitromethane followed by trapping with a wide range of nucleophiles effects C−C, C−O, C−N, C−S, and C−P bond formation.

The diynene lithium acetylide 5 adds to 2-siloxy-2-cyclohexenone 6 followed by silyl migration to produce ketone adduct 7 , an intermediate towards a simple Esperamicin core