Abstract: 2-Oxy-4H-3,1-benzoxazin-4-ones represented by the formula: ##STR1## and the pharmaceutically acceptable acid addition salts thereof, wherein: a is an integer of 0-4;A is a bond, or alkylene having one to eight carbon atoms;R is hydrogen, phenyl, imidazolyl or cycloalkyl having three to six carbon atoms, wherein the phenyl, imidazolyl or cycloalkyl ring is optionally substituted with 1-3 substituents independently selected from the group consisting of lower alkyl having one to four carbon atoms, lower alkoxy having one to four carbon atoms, --N(R.sup.1).sub.2, --NO.sub.2, halo or lower alkylthio having one to four carbon atoms, and,each R' is independently selected from the group consisting of lower alkyl having one to six atoms, lower alkenyl having two to six carbon atoms, lower alkoxy having one to six carbon atoms,lower alkylthio or halo-lower alkyl having one to four carbon atoms, halo, --NO.sub.2, --N(R.sup.1).sub.2, ##STR2## --NR.sup.1 COR.sup.2, and ##STR3## in which each R.sup.

Abstract: Compounds according to the formula ##STR1## an optical isomer thereof, or a pharmaceutically acceptable acid addition salt thereof wherein:n is an integer of 1 to 6;R.sub.1 is hydrogen or alkyl of 1 to 4 carbons;R.sub.2 is hydrogen or R.sub.1 and R.sub.2 are combined to form an oxo group;R.sub.3 is hydrogen, alkyl of 1 to 6 carbons, phenyl, benzyl, hydroxy lower alkyl or an aliphatic acylate thereof of 1 to 6 carbon atoms or an aryl acylate thereof of 7 to 12 carbon atoms, carbamoyl alkyl, carboxyalkyl, alkoxycarbonylalkyl of an .alpha.-amino acid side chain;R.sub.4 is hydrogen, alkyl of 1 to 6 carbons, benzyl, or hydroxy lower alkyl;Y is hydrogen, alkyl of 1 to 4 carbon atoms, halo or lower alkoxy;A is NR.sub.5 R.sub.6 wherein R.sub.5 and R.sub.

Abstract: Novel .alpha.-allenic-.alpha.-amino acids which are enzyme inhibitors of the suicide or k.sub.cat type are disclosed herein.

Abstract: Novel 2-amino-4H-3,1-benzoxazin-4-ones represented by the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and X are defined herein are useful as enzyme inhibitors in animals.

Abstract: Disclosed are compounds of the formula ##STR1## wherein the several groups are defined herein. These compounds are useful for treating inflammation.

Abstract: Compounds of the formula ##STR1## wherein n is 1-3; R.sup.1, R.sup.2 and R.sup.3 are the same or different and are hydrogen, lower alkyl, lower alkenyl, lower alkynyl, aryl or aryl lower alkyl wherein when aryl is phenyl it is unsubstituted or independently substituted with one or more halo, lower alkyl or lower alkoxy groups; and R.sup.4 is hydrogen, lower alkyl, lower alkenyl, lower alkynyl, trialkylsilyl, aryl or aryl lower alkyl wherein when aryl is phenyl it is unsubstituted or independently substituted by one or more halo, lower alkyl or lower alkoxy groups; excluding those compounds wherein R.sup.1 and R.sup.2 are hydrogen and R.sup.4 is ethyl, propyl or butyl. These compounds are useful as protease inhibitors.