Abstract: The invention relates to oligopeptide derivatives whose C-terminal amino acid is arginine which is linked to the remainder of an electroactive aniline or aminoquinoline derivative by an amide bond. The oligopeptide derivatives are split by enzymes of the class of peptide hydrolases, especially proteinases and their inhibitors, of the coagulation system, the fibrinolytic system and the complement system. These oligopeptide derivatives serve as substrates for quantitatively determining such enzymes, especially thrombin, in complex sample liquids, especially capillary blood. This determination is carried out by measuring the increase in the water-soluble amperogenic aniline or aminoquinoline compound. The oligopeptide derivatives and their salts can be produced according to usual methods in peptide chemistry.

Abstract: A method and composition for assaying protein C is described. The method comprises reacting a protein C-containing medium with a protein C-activating activator preparation obtained from venom of the snake Agkistrodon contortrix, or venom of another snake species which undergoes an immunological cross-reaction with the venom of Agkistrodon contortrix, to cause maximum activation of protein C and subsequently determining the quantity of activated protein C, said quantity being proportional to the amount of protein C in said medium. Also disclosed is a method and composition for treating thrombotic disorders with the activator preparation and a method of obtaining the activator preparation by culturing of a cloned microorganism.

Abstract: Peptide derivatives of formula ##STR1## wherein R.sup.1 represents a substituted amino group which is capable of being split off enzymatically with formation of a colored or fluorescent compound R.sup.1 -H. The said peptide derivatives are used for quantitatively assaying the enzyme C.sub.1 -esterase. The assaying is carried out by reacting a medium which contains C.sub.1 -esterase or in which the latter is formed or consumed with a peptide derivative as defined above and measuring photometrically, spectrophotometrically, fluorescence-spectrophotometrically or electrochemically the quantity of split product R.sup.1 -H released per time unit by the catalytic hydrolytic action of the said enzyme on the peptide derivative.

Abstract: A method for assaying blood coagulation factor XII in human blood plasma wherein plasma is treated with an activator in order to convert factor XII present in the plasma into factor XIIa, the latter is reacted with a tripeptide derivative which is split by the enzymatic action of factor XIIa and forms a colored or fluorescent split product, and the quantity of this split product is measured photometrically, spectrophotometrically or fluorescence-spectrophotometrically.

Abstract: Tripeptide derivatives which are useful as substrates for assaying proteolytic enzymes. The said derivatives are compounds of formulaH--D--X--Y--Z--Rwherein X represents a cyclohexylglycyl, cyclohexylalanyl, p-hydroxycyclohexylalanyl, phenylglycyl, phenylalanyl, tyrosyl, leucyl, isoleucyl, norleucyl, valyl, norvalyl, .alpha.-aminobutyryl, alanyl, prolyl or pipecolinoyl group, Y represents a cyclohexylglycyl, cyclohexylalanyl, p-hydroxycyclohexylalanyl, phenylglycyl, phenylalanyl or tyrosyl group and, if the meaning of X is limited to cyclohexylglycyl, cyclohexylalanyl, p-hydroxycyclohexylalanyl, phenylglycyl, phenylalanyl or tyrosyl, additionally a leucyl, isoleucyl, norleucyl, valyl, norvalyl, .alpha.-aminobutyryl, alanyl, prolyl or pipecolinoyl group, Z represents an arginyl or lysyl group and R represents a chromogenic group which can be split off by enzymatic hydrolysis and which is capable of forming a colored or fluorescent compound.

Abstract: A process for quantitatively assaying factor Xa from a medium by reacting the medium with tripeptide derivatives having the formula ##STR1## wherein R.sup.5 is a chromogenic substituted amino group capable of being split off by enzymatic hydrolysis to form a colored or fluorescent product H--R.sup.5. The quantity of split product H--R.sup.5 released by the enzymatic action on the tripeptide derivative is determined photometrically, spectrophotometrically, fluorescence-spectrophotometrically, or electrochemically. The quantity of released split product H--R.sup.5 per time unit is proportional to the quantity of enzyme present in the starting material.

Abstract: Tripeptide derivatives having the formula ##STR1## wherein R.sup.1 is alkanoyl or .omega.-aminoalkyanoyl, phenylalkanoyl or p-aminophenylalkanoyl, cyclohexylcarbonyl or 4-aminomethyl-cylcohexylcarbonyl, benzoyl optionally substituted with methyl, amino, or halogen in the o- or p-position, alkoxy carbonyl, benzyloxy carbonyl optionally substituted with methoxy, methyl, or chlorine in the p-position, alkylsulfonyl, phenylsulfonyl or naphthylsulfonyl, R.sup.2 is straight-chained or branched alkyl, hydroxyalkyl, alkoxyalkyl, benzoxyalkyl, .omega.-carboxy-alkyl, .omega.-alkoxy carbonylalkyl, .omega.-benzyloxycarbonylalkyl, cyclohexyl, cyclohexylmethyl, 4-hydroxycyclohexylmethyl, phenyl, benzyl, 4-hydroxybenzyl or imidazol-4-yl-methyl, R.sup.3 is hydrogen or alkyl, R.sup.4 is hydrogen, methyl or ethyl, and R.sub.5 is an amino group substituted with aromatic or heterocyclic radicals, R.sup.5 being capable of being split off by enzymatic hydrolysis to form a colored or fluorescent product H-R.sup.5.

Abstract: Tripeptide derivatives which are useful as substrates for assaying proteolytic enzymes. The said derivatives are compounds of formulaH--D--X--Y--Z--Rwherein X represents a cyclohexylglycyl, cyclohexylalanyl, p-hydroxycyclohexylalanyl, phenylglycyl, phenylalanyl, tyrosyl, leucyl, isoleucyl, norleucyl, valyl, norvalyl, .alpha.-aminobutyryl, alanyl, prolyl or pipecolinoyl group, Y represents a cyclohexylglycyl, cyclohexylalanyl, p-hydroxycyclohexylalanyl, phenylglycyl, phenylalanyl or tyrosyl group and, if the meaning of X is limited to cyclohexylglycyl, cyclohexylalanyl, p-hydroxycyclohexylalanyl, phenylglycyl, phenylalanyl or tyrosyl, additionally a leucyl, isoleucyl, norleucyl, valyl, norvalyl, .alpha.-aminobutyryl, alanyl, prolyl or pipecolinoyl group, Z represents an arginyl or lysyl group and R represents a chromogenic group which can be split off by enzymatic hydrolysis and which is capable of forming a colored or fluorescent compound.

Abstract: The present invention relates to a method for the quantitative determination of enzymes in human and mammal body fluids and tissue extracts, using a substrate which has the structureR.sup.1 --X--Y--Z--NH--R.sup.2wherein X represents a group having the formula ##STR1## in which R.sup.3 is a straight or branched alkyl radical having 1 to 7 carbon atoms or a cyclohexyl or cyclohexylmethyl radical, Y represents a seryl group or a group having the formula --NH--(CH.sub.2).sub.n --CO-- in which n is an integer from 1 to 7, Z represents an arginyl or lysyl group, R.sup.1 represents hydrogen or an acyl or sulfonyl group and R.sup.2 represents an aromatic hydrocarbon radical which optionally may carry substituents. The method includes measuring by photometric, spectrophotometric or fluorescence-photometric methods the quantity of the split product NH.sub.2 R.sup.2 formed by the hydrolytic action of the biologically active factors on the substrate.

Abstract: A substrate for the quantitative determination of enzymes in human and mammal body fluids and tissue extracts, which has the structureR.sup.1 --X--Y--Z--NH--R.sup.2wherein X represents a group having the formula ##STR1## in which R.sup.3 is a straight or branched alkyl radical having 1 to 7 carbon atoms or a cyclohexyl or cyclohexylmethyl radical, Y represents a seryl group or a group having the formula --NH--(CH.sub.2).sub.n --CO-- in which n is an integer from 1 to 7, Z represents an arginyl or lysyl group, R.sup.1 represents hydrogen or an acyl or sulfonyl group and R.sup.2 represents an aromatic hydrocarbon radical which optinally may carry substituents.