A FACILE SYNTHESIS OF NEW FUNGITOXIC IMIDAZO[2,1-B]-1,3,4-OXA(THIA)DIAZOLES AND IMIDAZO[2,1-B]THIAZOLES

2-amino heterocycles (1-5) containing the amino group as an element of a partial amidine structure reacted with trichloroacetyl chloride and then with primary arylamines to yield the title compounds (11-26) thr ough the ring closure of isolable N-heteroaryltrichloroacetamide inter mediates (6-10). Some of the intermediates were also prepared through an alternative pathway involving trichloroacetylphenoxyiminocarbonic c hloride. Three of the compounds (12, 18 and 21) displayed the in vitro fungitoxicity equivalent to that of a commercial fungicide mancozeb a gainst A. niger and F. oxysporium at 1000 ppm concentration.