Syntheses of stereochemically pure and selectively protected diamino diacids can be achieved by redox decarboxylation of distal N-hydroxyphthalimide esters of protected aspartic, glutamic or α-aminoadipic acids via radical addition to methylideneoxazolidinones. The products are useful for solidsupported syntheses of robust bioactive carbocyclic peptide analogs. Yields of reactive primary radical addition are superior to those of more stabilized radicals, and the reaction fails if the alkylideneoxazolidinone has a methyl substituent on its terminus (i.e., 13a/13b).

A modular synthesis of aspulvinones A, B, C, D, E, G and the recently isolated aspulvinone Q was developed. The methodology features a highly stereoselective aldol condensation of diazotetronic acid with aldehydes to provide 5-arylidene diazotetronates. Subsequent catalytic intermolecular C-H insertion reactions of the arylidene tetronates with arenes provide a series of naturally occurring aspulvinones including aspulvinones C, D and Q which have not been synthesized before. Variation of the aldehyde and the arene components furnishes synthetic analogues of the aspulvinones.

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Thieno[2,3-d]pyrimidin-4(3H)-ones with structures 11–38 were synthesized and some of them were found to be potent inhibitors of Mycobacterium tuberculosis H37Ra and/or Mycobacterium bovis BCG and non-toxic to human cell lines.