SYNTHETIC STUDIES ON PHENAZINE ANTIBIOTICS AND ANTHERIDIC ACID

In order to synthesize phenazine antibiotics with complex N-alkyl subs tituents, various types of activated alkylating reagents with or witho ut catalysts were examined to alkylate 1-trialkysiloxyphenazine 4. Amo ng them, halides-silver triflate and in situ prepared triflates from a lcohol and triflic anhydride were reagents of choice. Lavanducyanin 2 was synthesized via this procedure. The synthesis of benthocyanin A 10 is in progress. Starting from a chiral bicyclic building block 18, en antioselective synthesis of a pentacyclic antheridan skeleton was deve loped and the total synthesis of antheridic acid 17 is under investiga tion.