Oxoketene Dithiols: Synthesis of Some Heterocycles as Antimicrobials Utilizing Shrimp Chitin as a Natural Catalyst

GRAPHICAL ABSTRACT

Abstract

1, 2-dithiol 3-thione derivatives, as starting materials, were subjected to cycloaddition reactions in the presence of the dried outer shell of shrimp (chitin), under different reaction conditions to produce the 1, 3-dithiole-2-ylidene system. On treating 4-bromo dithiol 3-one, with dimethyl ester of acetylene dicarboxylic acid the bromo oxothiafulvene was produced. Further addition of DMAD to bromotrithiafulvene afforded the spiro bromo derivative. Trithiones and trithiafulvenes were also added to quinones, cyclohexadiene and cyclopentadiene monomer, and the corresponding adducts were produced through 1,3-dipole cycloaddition reactions. On testing some of the products against the isolated micro-organisms from sugar cane factory, the inhibition zones at concentration 1 × 10⁻⁶ were found. Products (2, 6, 9, 16, 23, 25, and 26) showed high activities against Bacillus sub., E.Coli and Asper. Niger.

Keywords:

• Gem-dithioacetals
• thiafulvenes
• trithiafulvenes
• ketoketene dithioles
• antimicrobs