Sparoxomycins A1 and A2, new inducers of the flat reversion of NRK cells transformed by temperature sensitive Rous sarcoma virus. II. Isolation, physico-chemical properties and structure elucidation

Total Syntheses of Sparsomycin and Sparoxomycins A1 and A2 via Sulfenate-Anion-Mediated Iterative C-S Bond Formation

The total synthesis of the pyrimidinylpropenamide antibiotics sparsomycin and sparoxomycins A1 and A2 has been achieved. The synthesis of sparsomycin relies on the iterative nucleophilic attack of sulfenate anions on alkyl halides to construct the dithioacetal monoxide chain with high diastereoselectivity. Subsequently, the reagent-controlled diastereoselective oxidation of the terminal sulfide moiety of sparsomycin directly provides sparoxomycins A1 and A2.

Pyrimidine as constituent of natural biologically active compounds

This review describes the various manifestations of the pyrimidine system (alkylated, glycosylated, benzo-annelated.). These comprise pyrimidine nucleosides as well as alkaloids and antibiotics--some of them have been discovered and isolated from natural sources already long time ago, others have been reported very recently. A short overview on pyrimidine syntheses (prebiotic synthesis, biosynthesis, and metabolism) is given. The biological activities of most of the pyrimidine analogs are briefly described, and, in some cases, syntheses are formulated.

Synthesis and morphological reversion activity on srctsNRK cells of pyrimidinylpropanamide antibiotics, sparsomycin, sparoxomycin A1, A2, and their analogues

Three pyrimidinylpropanamide antibiotics sparsomycin (1), sparoxomycins A1, A2 (2, 3), and also six analogues (4-9) have been synthesized by employing asymmetric sulfide oxidation conditions as a key step. Sparsomycin (1) and its alkyl analogues (5-7) showed higher morphological reversion activities on srctsNRK cells than 2 and 3.