6,7-Dihydro-8H-pyrrolo[2,1-c][1,4]thiazine-1(8aH),4(3H)-dione
6- or 7- (2-imino-2-imidazolidine)-1,4-benzoxazines as .alpha. a
6-(substituted methylene) penems and intermediates
6-Aryluracils
6-benzoxazinyl- and 6-benzothiazinyl 2,3,4,5-tetrahydropyridazin
6-benzoxazinyl-2,3,4,5-tetrahydropyridazin-3-ones
6-Loweralkoxy or loweralkylthio-3-cephem-4-carboxylic acids
6H-pyrazolo-[4,5,1-d,e]acridin-6-one derivatives having anit-tum