This paper is dedicated to Henk van der Plas who has for many years inspired heterocyclic chemists the world over with his innovative research, his impeccable standards and his charming personality Abstract propan-N-(2,2,2-trichloroethoxysulfonyl)guanidine was synthesized from 3-formyl-1-methylindole in six steps and subjected to conditions intended to convert the side-chain into a 2-iminotetrahydropyrimidine-containing product, of relevance to a possible synthesis of the aplicyanins. An

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... tive reaction course was observed, resulting in the formation of a new tetracyclic system. Recently, a new family of five antitumor agents, the aplicyanins, 1, was isolated from an Antarctic ascidian Aplidium cyaneum, 1 for example aplicyanin A has R 1 =R 2 =R 3 =H, aplicyanin B has R 1 =Ac, R 2 =R 3 =H, and the most complex, aplicyanin F has R 1 =Ac, R 2 =OMe, R 3 =Br. Following our studies on the synthesis of a variety of heterocyclic marine natural products 2 and derivatives 3 we were attracted to the synthesis of such structures and describe here our initial model study aimed at constructing a 4-(indol-3-yl)tetrahydropyrimidine. Our plan was to construct the reduced pyrimidine unit, following the recent work by Du Bois et al. 4 However, an Issue in Honor of Prof Henk C. van der Plas ARKIVOC 2009 (vi) 260-269