Abstract: Compounds useful in the preparation of pharmaceutical preparations for the treatment of microbial infection where such compounds are of structural Formula I ##STR1## or pharmaceutically acceptable salts thereof wherein: R.sup.1 is --CHO, --COCH.sub.3, --COCHCl.sub.2, --COCHF.sub.2, --CO.sub.2 CH.sub.3, --SO.sub.2 CH.sub.3, or --COCH.sub.2 OH; X.sup.1 and X.sup.2 are independently H, F, or Cl; and Q is a five membered ting heterocycle (azolyl ring) of the general form: ##STR2## wherein A, B, and C are independently oxygen (O), nitrogen (N), sulfur (S) or Carbon (C). In all cases, the piperazine nitrogen atom is attached at the carbon atom of the carbon-nitrogen double bond.

Abstract: The present invention provides for new 5-amidomethyl, .alpha.,.beta.-saturated and--unsaturated butyrolactone antibacterial agents of formula I ##STR1## characterized by 3-aryl substituents that include, for example, indolinyl and phenyl substituted with zero (0) to two(2) halogen atoms and substituted in the para position with, e.g., piperazinyl, thiomorpholinyl (and corresponding sulfoxide and sulfone), thiazolidinyl (and sulfoxide and sulfone), morpholinyl, azetidinyl, pyrrolidinyl, piperidinyl, pyrrolyl, azepinyl, troponyl, 3,7-diazabicyclo?3.3.0!octan-3-yl, bridged thiazinyl or bridged oxazinyl moieties. In those cases where a ring nitrogen is present, then this is substituted to form an amide, formamide, sulfonamide, urethane, or alkylated with a wide variety of moieties.