Abstract: A following dipeptide derivative of the following formula (I) is provided, which is capable of inhibiting the enzymatic activity of renin and thereby depressing the renin-angiotensin system and lowering the blood pressure. ##STR1## wherein: R.sup.1 is C.sub.1 -C.sub.12 alkyl, C.sub.2 -C.sub.6 alkenyl, C.sub.2 -C.sub.6 alkynyl, C.sub.3 -C.sub.10 cycloalkyl, aryl, or heterocyclic radical;R.sup.2 is carbamoyl, aryl, 5- or 6-membered heterocyclic radical, C.sub.1 -C.sub.12 alkyl-S--, C.sub.1 -C.sub.12 alkyl-S--CH.sub.2 --, or C.sub.3 -C.sub.10 cycloalkyl-S--;R.sup.3 is aryl or 5- or 6-membered heterocyclic radical;R.sup.4 is R.sup.4' --SO.sub.2 or R.sup.4' --CO;R.sup.4' is aryl, C.sub.1 -C.sub.12 alkyl, C.sub.2 -C.sub.6 alkenyl, C.sub.2 -C.sub.6 alkynyl; C.sub.3 -C.sub.10 cycloaklyl, or heterocyclic radical;X is CH.sub.2, NH, O, or S; andY is CO or NHSO.sub.2, wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4' each may be substituted with one to three substituents.

Abstract: A dipeptide derivative of the formula (I) is provided, which is capable of inhibiting the enzymatic activity of renin and thereby depressing the renin-angiotensin system and lowering the blood pressure, provided. ##STR1## wherein: R.sup.1 is C.sub.1 -C.sub.12 alkyl, C.sub.2 -C.sub.6 alkenyl, C.sub.2 -C.sub.6 alkynyl, C.sub.3 -C.sub.10 cycloalkyl, aryl, or heterocyclic radical;R.sup.2 is carbamoyl, aryl, 5- or 6-membered heterocyclic radical, C.sub.1 -C.sub.12 alkyl-S--, C.sub.1 -C.sub.12 alkyl-S--CH.sub.2 -, or C.sub.3 -C.sub.10 cycloalkyl-S-;R.sup.3 is aryl or 5- or 6-membered heterocyclic radical;R.sup.4 is R.sup.4' --SO.sub.2 or R.sup.4' --CO;R.sup.4' is aryl, C.sub.1 -C.sub.12 alkyl, C.sub.2 -C.sub.6 alkenyl, C.sub.2 -C.sub.6 alkynyl; C.sub.3 -C.sub.10 cycloalkyl, or heterocyclic radical;X is CH.sub.2, NH, O, or S; andY is CO or NHSO.sub.2, wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4' each may be substituted with one to three substituents.

Abstract: A dipeptide derivative of formula (I) is provided, which is capable of inhibiting the enzymatic activity of renin and thereby depressing the renin-angiotensin system and lowering the blood pressure. ##STR1## wherein: R.sup.1 is C.sub.1 -C.sub.12 alkyl, C.sub.2 -C.sub.6 alkenyl, C.sub.2 -C.sub.6 alkynyl, C.sub.3 -C.sub.10 cycloalkyl, aryl, or heterocyclic radical;R.sup.2 is carbamoyl, aryl, 5- or 6-membered heterocyclic radical, C.sub.1 -C.sub.12 alkyl-S--, C.sub.1 -C.sub.12 alkyl-S--CH.sub.2 --, or C.sub.3 -C.sub.10 cycloalkyl-S--;R.sup.3 is aryl or 5- or 6-membered heterocyclic radical;R.sup.4 is R.sup.4' --SO.sub.2 or R.sup.4' --CO;R.sup.4' is aryl, C.sub.1 -C.sub.12 alkyl, C.sub.2 -C.sub.6 alkenyl, C.sub.2 -C.sub.6 alkynyl; C.sub.3 -C.sub.10 cycloalkyl, or heterocyclic radical;X is CH.sub.2, NH, O, or S; andY is CO or NHSO.sub.2, wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4' each may be substituted with one to three substituents.

Abstract: Highly effective diuretic antihypertensives, i.e., sulfamoyl-2-benzofurancarboxylic acid derivatives which are classified as loop diuretics with less adverse side-effects and can be administered orally at a daily dosage of 0.5 mg to 200 mg or parenterally at 0.01 mg to 50 mg.

Abstract: Highly effective diuretic antihypertensives, i.e., 2,3-dihydrobenzofuran-5-sulfonamide derivatives which is classified to loop diuretics with less adverse side-effects and can be administered orally at a daily dosage of 0.5-200 mg or parenterally of 0.01-50 mg.

Abstract: Highly safe new diuretics, i.e., 1,4-benzodioxane and 1,4-benzodioxine derivatives having potent antihypertensive activity but no or little uricesuric activity, which can be administered to human orally, intravenously, or hypodermically at a respective daily dosage of 0.1-2 mg/kg, 0.005-0.1 mg/kg, or 0.02-0.4 mg/kg.

Abstract: The disclosed peptide derivative of the formula:Y--Tyr--Gly--RWherein, Y represents a hydrogen atom or an amino protecting group, Tyr represents a tyrosine residue wherein at least one of the hydrogen atoms on the phenyl ring may be substituted by a radioactive iodine, Gly represents a glycine residue, and R represents a peptide residue corresponding to an amino acid sequence which includes at least positions 7 through 21 of human proinsulin C-peptide proves to be useful for determining C-peptide level in human serum.