Synthesis and antimicrobial investigations of some 4-arylideneamino-3-(alpha,alpha-diphenyl-alpha-hydroxy-methyl)-1,4-dihydro-5H-1,2,4-triazo-5-thiones and 6-arene-3-(alpha,alpha-diphenyl-alpha-hydroxymethyl)-7H-s-triazolo[3,4-b][1,3,4]thiadiazines