Abstract: 2,4-Diaminoquinazoline compounds of the formula ##STR1## or a pharmaceutically acceptable salt thereof wherein R is a pyrimidinyl, pyrazinyl, pyridazinyl or triazinyl group linked to the piperazine ring by one of its carbon atoms, and optionally substituted by hydroxy, halogen, alkyl, aralkyl, alkoxy, aralkoxy,alkylthio, aryl, aryloxy and certain amino groups; their use as an antihypertensive agent and pharmaceutical compositions containing them.

Abstract: 2,4-Diaminoquinazoline compounds of the formula ##STR1## or a pharmaceutically acceptable salt thereof wherein R is a pyrimidinyl, pyrazinyl, pyridazinyl or triazinyl group linked to the piperazine ring by one of its carbon atoms, and optionally substituted by hydroxy, halogen, alkyl, aralkyl, alkoxy, aralkoxy, alkylthio, aryl, aryloxy and certain amino groups; their use as an antihypertensive agent and pharmaceutical compositions containing them.

Abstract: 2,4-Diaminoquinazoline compounds of the formula ##STR1## or a pharmaceutically acceptable salt thereof wherein R is a pyrimidinyl, pyrazinyl, pyridazinyl or triazinyl group linked to the piperazine ring by one of its carbon atoms, and optionally substituted by hydroxy, halogen, alkyl, aralkyl, alkoxy, aralkoxy, alkylthio, aryl, aryloxy and certain amino groups; their use as an antihypertensive agent and pharmaceutical compositions containing them.

Abstract: Regulators of the cardiovascular system and, in particular, in the treatment of hypertension having the formula ##STR1## wherein R is lower alkyl;X, is a 3- or 4-position substituent and is --(CH.sub.2).sub.n CONR.sup.1 R.sup.2, --O(CH.sub.2).sub.n CONR.sup.1 R.sup.2 or ##STR2## wherein n is 0, 1 or 2;R.sup.1 is hydrogen or lower alkyl, andR.sup.2 is lower alkyl; lower alkenyl, lower alkynyl, phenyl, substituted phenyl, C.sub.3 -C.sub.7 cycloalkyl; lower alkyl substituted by phenyl, substituted phenyl, C.sub.3 -C.sub.7 cycloalkyl, halogen, trifluoromethyl, hydroxy, lower alkoxy, lower alkoxycarbonyl, phenoxy, substituted phenoxy or --NR.sup.3 R.sup.4 wherein R.sup.3 and R.sup.4 each represent hydrogen, lower alkyl, lower alkanoyl or lower alkylsulfonyl; with the proviso that any O, N or halogen atom in R.sup.2 is separated by at least 2 carbon atoms from the nitrogen atom to which R.sup.2 is attached; orR.sup.1 and R.sup.

Abstract: Certain 2-deoxystreptamine aminoglycoside antibiotics, substituted on the 1-amino group by an alkyl group bearing one or more hydroxy groups, are useful antibacterial agents. The 2-deoxystreptamine aminoglycoside compounds which are substituted in this manner include the kanamycins, the gentamicins, tobramycin, ribostamycin, the neomycins, and 6'-N-alkyl derivatives thereof.

Abstract: Derivatives of kanamycin A, which have an acyl protecting group on the C-3" and C-6' amino groups, and optionally have a benzyl protecting group on the C-3 amino group, are useful intermediates for the preparation of 1-N-(.omega.-amino-2-hydroxyalkyl) derivatives of kanamycin A. Derivatives of kanamycin B, which have an acyl protecting group on the C-2', C-3" and C-6' amino groups, and optionally have a benzyl protecting group on the C-3 amino group, are useful intermediates for the preparation of 1-N-(.omega.-amino-2-hydroxyalkyl) derivatives of kanamycin B. Certain of the partially protected kanamycin A and kanamycin B derivatives of this invention are useful for preparing 1-N-(.omega.-amino-2-hydroxyalkanoyl) derivatives of kanamycin A and B. 1-N-(.omega.-Amino-2-hydroxyalkyl) and 1-N-(.omega.-amino-2-hydroxyalkanoyl)derivatives of kanamycin A and B are known antibacterial agents.