Dedicated to Professor Gerhard Spiteller on the occasion of his 85th birthday.The first total synthesis of makaluvamine O and batzelline D, pyrroloquinoline alkaloids isolated from marine sponges, are described. Key steps in the biomimetic synthesis are an intramolecular Michael addition leading to the pyrrolo[4,3,2-de]quinoline core and the following selective halogenation at C-6 position with NBS/NCS. Moreover, the related marine alkaloids damirone C, makaluvone and batzelline C were synthesised via this approach.

Elaborate fragments of the proposed stereostructure of the complex polyketide antibiotic vancoresmycin have been synthesized in a stereoselective fashion based on a modular and convergent approach. Significant nuclear magnetic resonance differences in one of these subunits compared with the natural product question the proposed stereoconfiguration. Consequently, an extensive bioinformatics analysis of the biosynthetic gene cluster was carried out, leading to a revised stereoconfigurational proposal for this highly potent antibiotic.