Abstract: According to the present invention, there are provided a monoclonal antibody to prostate-derived acid phosphatase and a method for determination of prostate-derived acid phosphatase using the monoclonal antibody. Prostate-derived acid phosphatase is boostered in animal and spleen cells isolated from the animal are fused with myeloma cells. The hybridoma capable of producing a monoclonal antibody having extremely high specificity to prostate-derived acid phosphatase is subjected to cloning. Using the monoclonal antibody produced by the hybridoma, prostate-derived acid phosphatase in a sample can be detected with extremely high sensitivity.

Abstract: Novel tripeptide derivatives having a pyroglutamic acid residue strongly inhibit a plurality of trypsin-like serine proteases such as plasmin, thrombin, trypsin, kallikrein, factor Xa and urokinase. The compounds of the present invention can inhibit various trypsin-like serine proteases and are expected to show remarkable effects as novel protease inhibitors for the treatment of pancreatitis, inflammantion, ulcer, etc.

Abstract: Novel N.sup.G -protected or unprotected-L-argininal-dibutyl acetals (I) can be prepared from L-argininal derivatives (III) merely by reacting in an azeotropic solvent in the presence of p-toluenesulfonic acid. In the products (I), L-form amounts to more than 99%, without further optical resolution. The L-argininal acetals (I) are useful as starting materials for preparing peptidyl-L-argininal derivatives which can provide protease inhibitors or ligands used for affinity chromatography of various proteases.

Abstract: Novel N-acetyl-.beta.-D-glucosamine derivatives and a method for assaying N-acetyl-.beta.-D-glucosaminidase activity using the same as substrate are provided.N-Acetyl-.beta.-D-glucosamine derivatives represented by general formula (I): ##STR1## wherein each of R.sub.1 and R.sub.2 independently represents hydrogen atom or methyl or ethyl group, are mixed with a sample containing N-acetyl-.beta.-D-glucosaminidase (NAG) and then absorbance of the reaction solution is determined to assay NAG activity extremely accurately.

Abstract: Phosphoric acid derivatives represented by formula (I): ##STR1## wherein X is a halogen and R is --(CH.sub.2).sub.n CH.sub.3 (n=0 to 3), or salts thereof are stable to non-enzymatic hydrolysis and are capable of specifically reacting with acid phosphatase. Therefore, the activity of acid phosphatase in the sample can be determined extremely accurately by reacting said compound with a sample containing acid phosphatase and quantitatively determining the reaction product by colorimetry.

Abstract: Tripeptide derivatives of formula (I) such as N-.epsilon.-(p-tosyl)-D-lysyl-L-prolyl-L-argininal have an activity of inhibiting a plurality of trypsin-like serine proteases, e.g., plasmin, thrombin, trypsin, kallikrein, factor Xa, urokinase, etc. in vivo. The tripeptide derivatives can be expected as novel protease inhibitors due to their remarkable pharmaceutical effects.

Abstract: There is provided a method for determination of hydroxyacetophenone derivatives such as 3,5-dichloro-4-hydroxyacetophenone in the presence of protein such as albumins or globulins with high sensitivity. The hydroxyacetophenone derivative can be measured in the neutral to acidic region, whereby the method is not affected by interferrants such as bilirubin or hemoglobin. The hydroxyacetophenone derivatives are useful as the chromogen of synthetic substrates for determining acid phosphatase activity.

Abstract: Compounds represented by the following formula: ##STR1## wherein A.sub.1 and A.sub.2 each represents a specific amino acid residue, are excellent as substrates for determination of enzyme activity such as trypsin, etc.

Abstract: Novel compounds represented by the following formula: ##STR1## wherein A represents a specific amino acid residue are excellent as substrates for determination of enzyme activity such as trypsin, etc. The compounds can be synthesized from novel arginyl-3-tert-alkyloxycarbonyl-4-nitroanilides by a novel process comprising a selective deprotection step whereby the protecting group on the .alpha.-amine group of arginine is removed in the presence of a hydrochloric acid, acetic acid and dimethylformamide mixture, but a tert-alkyl protecting group on the --COOH group of the nitroanilide ring is not removed by this step.

Abstract: Phosporic acid derivatives represented by formula (I): ##STR1## wherein X is a halogen and R is --(CH.sub.2).sub.n CH.sub.3 (n=0 to 3), or salts thereof are stable to non-enzymatic hydrolysis and are capable of specifically reacting with acid phosphatase. Therefore, the activity of acid phosphatase in the sample can be determined extremely accurately by reacting said compound with a sample containing acid phosphatase and quantitatively determining the reaction product by colorimetry.

Abstract: A synthetic peptide of the formula: H-.sub.D -A.sub.1 -Leu-Lys-NH ##STR1## wherein A.sub.1 is Pro or Ala, is excellent in solubility in water and substrate specificity and is suitable as a substrate for determining trypsin and .alpha..sub.1 -antitrypsin.

Abstract: A synthetic peptide of the formula: ##STR1## wherein A.sub.1 is Pro or Ala, is excellent in solubility in water and substrate specificitity and is suitable as a substrate for determining trypsin and .alpha..sub.1 -antitrypsin.

Abstract: Tripeptide derivatives of the formula:A--aaa(B)--Phe--Lys--C (I)wherein A, B and C are each one of a specific range of substituents, and aaa, Phe and Lys are each of a specific range of amino acid residues, are potent inhibitors of plasmin and useful for prevention or suppression of hemorrhage and for inhibition of the progress of inflammation.

Abstract: This invention relates to a method for determination of cholinesterase activity, characterized by using, as a substrate, a choline derivative represented by the general formula (I): ##STR1## wherein X is a halogen atom; Y.sub.1 is a hydroxyl group as a substituent in the 2- or 5-position; and Y.sub.2 is a hydroxyl group as a substituent in the 3-position.The determination method of this invention permits easy and simple determination of cholinesterase activity, and is very useful as a determination method for clinical examinations for the purpose of determining cholinesterase in serum.

Abstract: Novel compounds represented by the following general formula (1) and salts thereof: ##STR1## wherein n represents an integer of 3 to 4, R.sup.1 represents ##STR2## or --SO.sub.2 R.sup.2, and R.sup.2 represents optionally branched lower alkyl group having 1 to 6 carbon atoms, phenyl group, benzyl group or tolyl group, which are useful as substrate for use in the measurement of biological components; a substrate for use in the measurement of biological component which comprises said novel compound or salt thereof; and a method for measuring biological component which comprises using said substrate.

Abstract: In a method for determining cholinesterase (hereinafter referred to as ChE) activity, the improvement comprising by using, as a substrate, a protocatechuoylcholine derivative represented by the general formula (I), ##STR1## (wherein X is a halogen atom). The method for determining ChE activity according to the present invention is free from defects of the conventional methods, has many advantages and characteristics, permits accurate and simple determination of ChE activity, and can sufficiently contribute to determination of ChE activity in daily clinical examinations.

Abstract: A novel chromogenic and fluorescent substrate for measuring the concentration of kallikrein in urine. The novel substrate according to the present invention has very excellent substrate specificity to kallikreins and good solubility in water or biological test solutions.The present substrate is therefore useful for measuring the concentration of kallikrein in urine for the diagnosis of hypertension and other diseases caused by the lowering of the concentration of kallikrein.

Abstract: A novel chromogenic and fluorescent substrate for determining the activity of blood coagulation factor Xa and Xa-like enzymes. The novel substrate according to the present invention has very excellent selectivity as compared with the hitherto disclosed substrates and enables specific determination of blood coagulation factor Xa. The present substrate is therefore useful for the studies of chemical reactions involving formation, inhibition and consumption of factor Xa and can be also used for the determination of various factors associated therewith such as factor X, anti-Xa factor, factor VII, factor VIII, factor IX and heparin.

Abstract: A method for measuring the activity of plasmin in plasma which comprises reacting a compound of the following formula or a salt thereof; ##STR1## with plasmin in a buffer solution having a pH of 7.2 to 7.6 and quantitatively determining the reaction product thereof.

Abstract: Novel arginyl-3-carboxy-4-hydroxyanilide of the formula ##STR1## and acid addition salts thereof are of use as starting materials for preparing chromophoric and fluorescent substrates for measurement of enzyme activity.