Abstract: Novel compounds of the formula ##STR1## wherein the, substituents are defined as in the specification and their non-toxic, pharmaceutically acceptable salts which inhibit the effects of angiotensin II in warm-blooded animals.

Abstract: Substituted pyrazole dimers are useful in prophylaxis and treatment of influenza virus infections.

Abstract: The invention relates to benzimidazoles of general formula ##STR1## wherein R.sub.1 to R.sub.4 are as defined herein, the 1-, 3-isomer mixtures thereof and the addition salts thereof. The new compounds are useful, in particular, as angiotensin antagonists.

Abstract: This invention relates to compounds which inhibit thrombin or factor Xa. The compounds contain an aldehyde functionality and a methionine sulfone or S-substituted cysteine sulfone residue. The compounds and their pharmaceutical compositions are useful for preventing thrombosis in mammals which are suspected of having a condition characterized by abnormal thrombosis.

Abstract: Compounds of the formula ##STR1## where the symbols have the meaning defined in the specification have retinoid-like biological activity.

Abstract: Conformationally restricted compounds are described which are therapeutically effective as angiotensin II antagonists for the treatment of circulatory disorders.

Abstract: Compounds of formula (I), wherein A is selected from (a), (b), (c), (d), (e), (f) and B is selected from (g), (h), and (i), wherein W is a carbonyl, sulphonyl or sulphinyl group, and X is a carbonyl, sulphonyl or sulphinyl group or --C(O)--CH.sub.2 -- (in which the carbonyl group is bonded to Y), provided that at least one of W and X contains carbonyl, Y is R.sub.9 --O-- or R.sub.9 --N(R.sub.10)--, Z is selected from (i), (ii), (iii), (iv) or Z is absent and W is H, with a number of provisions and phamaceutically acceptable salts thereof are ligands at CCK and/or gastrin receptors.

Abstract: The present invention is directed to certain compounds of the general structural formula: ##STR1## wherein R.sub.1, R.sub.1a, R.sub.2a, R.sub.3, R.sub.3a, R.sub.4, R.sub.5, R.sub.6, A, W, and n are as defined herein. These compounds promote the release of growth hormone in humans and animals. This property can be utilized to promote the growth of food animals to render the production of edible meat products more efficient, and in humans, to treat physiological or medical conditions characterized by a deficiency in growth hormone secretion, such as short stature in growth hormone deficient children, and to treat medical conditions which are improved by the anabolic effects of growth hormone. Growth hormone releasing compositions containing such compounds as the active ingredient thereof are also disclosed.

Abstract: The invention concerns heterocyclic compounds of the general formula (I) in which A, B, R, R.sup.2, R.sup.3, W, Y, Z.sup.1, Z.sup.2 and r are as defined in the description, methods of preparing them and their use as inhibitors of thrombocyte aggregation, the metastization of carcinoma cells and the binding of osteoclasts on bone surfaces.

Abstract: This invention relates to compounds which inhibit thrombin or factor Xa. The compounds contain an aldehyde functionality and a methionine sulfone or S-substituted cysteine sulfone residue. The compounds and their pharmaceutical compositions are useful for preventing thrombosis in mammals which are suspected of having a condition characterized by abnormal thrombosis.

Abstract: Abstract of the Disclosure: Diphenylheteroalkyl derivatives of the formula I ##STR1## where A and R.sup.1 -R.sup.6 have the meanings specified in the description, and the preparation thereof are described.The substances are suitable for controlling diseases and as cosmetic agents.

Abstract: Derivatives of 9-deazaguanine are prepared by reacting an aldehyde or ketone with a dialkylaminomalonate to form the corresponding enamine. The enamine is then reacted with a base to form a cyclic pyrrole. The cyclic pyrrole is reacted with an urea compound to provide a protected guanidino compound. The guanidino is converted to the desired 9-deazaguanine derivative by reacting with trifluoracetic acid or with an alkoxide or hydroxide followed by neutralization with an acid.

Abstract: Dialkyl ethers lower Lp(a) and triglycerides, and elevate HDL-cholesterol, and are thereby useful for treating vascular diseases and noninsulin-dependent diabetes mellitus.

Abstract: An angiotensin II antagonist of the formula: ##STR1## in which: R.sub.p.sup.1 represents hydrogen, C.sub.1 -C.sub.6 alkyl, C.sub.3 -C.sub.6 cycloalkyl or C.sub.1 -C.sub.6 alkanoyl; R.sub.p.sup.2 represents a single bond, C.sub.1 -C.sub.4 alkylene or C.sub.1 -C.sub.4 alkylidene; R.sub.p.sup.3 and R.sub.p.sup.4 are independently selected from the group consisting of hydrogen and C.sub.1 -C.sub.6 alkyl; R.sub.p.sup.5 represents hydrogen, C.sub.1 -C.sub.4 alkyl, phenyl, naphthyl, benzyl, diphenylmethyl, naphthylmethyl, alkanoyloxyalkyl, cycloalkanecarbonyloxyalkyl, alkoxycarbonyloxyalkyl, cycloalkyloxycarbonyloxyalkyl, (5-phenyl-2-oxo-1,3-dioxolen-4-yl)methyl, (5-alkyl-2-oxo-1,3-dioxolen-4-yl)methyl or phthalaidyl; R.sub.p.sup.6 represents a carboxy or a tetrazol-5-yl; and X.sub.p represents an oxygen or sulfur, and pharmaceutically acceptable salts thereof. The compounds have hypotensive activity and can thus be used for the treatment and prophylaxis of hypertension.

Abstract: The invention concerns diazapentalene derivatives of formula I ##STR1## in which X and Y represent leaving groups which are less nucleophilic than thiol compounds, as thiol-specific fluorochromes for the detection of compounds containing thiol groups, in particular in cells.

Abstract: Pharmaceutically useful compounds having ACAT inhibitory activity of the formula ##STR1## wherein n is 0, 1, or 2, for X other than tetrazole and n=2 then R.sub.2 .dbd.R.sub.3 .dbd.H; R.sub.1 is phenyl, substituted phenyl, naphthyl, substituted naphthyl, a heteroaromatic group or a hydrocarbon group having from one to 18 carbon atoms; R.sub.2 and R.sub.3 are hydrogen, halo, hydroxy, alkyl, alkenyl, cycloalkyl, phenyl, substituted phenyl, a heteroaryl, or form a spiroalkyl group; X is a heteromonocyclic 5-membered ring containing one to four heteroatoms, said heteroatoms being nitrogen, oxygen or sulfur, and combination thereof; and R.sub.4 is a hydrocarbon group having from one to 20 carbon atoms are described as well as methods of their manufacture.

Abstract: Compounds of formula I ##STR1## wherein R.sub.1 is a 2-R.sub.A -3-R.sub.B -phenyl radical, a 2-R.sub.A -4-R.sub.C -phenyl radical, a 2-R.sub.A -pyridin-3-yl radical, a 3-R.sub.A -pyridin-2-yl radical or a 1-R.sub.D -indol-3-yl radical, wherein one of the radicals R.sub.A and R.sub.B is an aliphatic or heterocycloaliphatic-aliphatic radical or free or aliphatically, araliphatically or heteroaraliphatically etherified hydroxy and the other is hydrogen, an aliphatic radical or free or esterified or amidated carboxy, R.sub.C is hydrogen, an aliphatic radical, free or aliphatically, araliphatically, heteroaraliphatically or heteroarylaliphatically etherified hydroxy or an unsubstituted or heteroaliphatically substituted amino group, and R.sub.D is an aliphatic, araliphatic or heteroaliphatic radical, one of the radicals X.sub.1 and X.sub.2 is carbonyl and the other is methylene, R.sub.2 is an aliphatic radical, R.sub.3 is unsubstituted or aliphatically substituted amino, R.sub.

Abstract: "Esters" are synthesized by reacting a nucleophile with a propargyl xanthate advantageously having the formula (I):R.sub.3 --C.tbd.C--CR.sub.1 R.sub.2 --S--CS--Y--R (I)in the presence of at least one acid, Bronsted or otherwise, and at a temperature ranging from 0.degree. to 300.degree. C.; the subject reaction is particularly applicable to a wide variety of chiral organic syntheses.

Abstract: This appliciation discloses a process for preparing a lactone of general formula (I), where R is an optionally substituted phenyl group or an optionally substituted mono- or bicyclic heteroaryl radical which process comprises reacting an anion of a malonate of formula (II) with an ethylene compound of formula (III) Y--CH.sub.2 --CH.sub.2 OZ, to give a compound of formula (IV) and hydrolysing the compound of formula (IV) to give a lactone of formula (I). The lactones are of use as intermediates for preparing 5-HT.sub.1A binding agents.

Abstract: The present invention relates to a process for the preparation of the 2-n.butyl-3-[[2'-(tetrazol-5-yl)biphenyl-4-yl]methyl]-1,3-diazaspiro [4.4]-non-1-en-4-one by reaction of the corresponding nitrile with an alkaline azide and triethylamine hydrochloride, recovering the 2-n.butyl-3-[[2'-(tetrazol-5-yl)biphenyl-4-yl]methyl]-1,3-diazaspiro[4.4]n on-1-en-4-one in form of one of its alkaline salts in aqueous solution, by neutralization of said alkaline salt and crystallization of the 2-n.butyl-3-[[2'-(tetrazol-5-yl)-biphenyl-4-yl]methyl]-1,3-diazaspiro[4.4] non-1-en-4-one thus precipitated either in a solvent containing less than 10% of water or in a solvent containing more than 10% of water in order to obtain two differents crystalline forms. Furthermore a novel crystalline form of 2-n.butyl-3-[[2'-(tetrazol-5-yl)biphenyl-4-yl]methyl]-1,3-diazaspiro[4.4] non-1-en-4-one and pharmaceutical compositions containing it are described.

Abstract: Amidinophenylalanine derivatives of the formula I ##STR1## the synthesis of these compounds, the use thereof and pharmaceutical agents which contain these compounds are described.

Abstract: The invention relates to N-acyl-N-heterocyclylalkylamino acids of the formula ##STR1## wherein Y.sub.1 is O, S or N(R) and R is hydrogen or C.sub.1 -C.sub.7 alkyl;X.sub.1 is --CO-- or --S(O).sub.m -- and the index m is 0, 1 or 2;one of the variables X.sub.2 and X.sub.4 is C.sub.1 -C.sub.4 alkylene and the other of the variables X.sub.2 and X.sub.4 is a bond; or each of the variables X.sub.2 and X.sub.4 is a bond;X.sub.3 is C.sub.3 -C.sub.7 cycloalkylidene or the structural element --C(X.sub.a)(X.sub.b)-- and X.sub.a is hydrogen or C.sub.1 -C.sub.7 alkyl and X.sub.b is C.sub.1 -C.sub.7 alkyl;and the rings A, B and C, with the exception of the substituents indicated in the formula, and also aromatic substituents are, independently of one another, unsubstituted or mono- or poly-substituted by substituents selected from the group consisting of halogen, C.sub.1 -C.sub.7 alkyl, C.sub.1 -C.sub.7 alkoxy, C.sub.2 -C.sub.7 alkenyloxy, phenoxy, benzyloxy, trifluoromethyl and S(O).sub.

Abstract: Biphenyl derivatives and processes for the preparation of biphenyl derivatives are described. A compound of formula (I) is disclosed ##STR1## in which the substituent X is --CHO or --CH(OR.sup.1)OR.sup.2, where R.sup.1 and R.sup.2 independently of one another are (C.sub.1 -C.sub.6)-alkyl or R.sup.1 and R.sup.2 together are an alkylene group (--CH.sub.2).sub.n --, where n is 2, 3 4 or 5 and R is --F, --Cl, --NO.sub.2, --(CH.sub.2).sub.m --COOR.sup.3, --(CH.sub.2).sub.m --CONHR.sup.3, --(CH.sub.2).sub.m --CN, --SO.sub.2 NH--COOR.sup.3, --SO.sub.2 NH--CO--NHR.sup.3, --SO.sub.2 NH--SO.sub.2 --R.sup.3, --NHSO.sub.2 R.sup.3, ##STR2## --PO.sub.3 R.sup.3, --NH--SO.sub.2 --CF.sub.3, --SO.sub.2 NR.sup.4 where R.sup.3 is hydrogen, (C.sub.1 -C.sub.6)-alkyl, (C.sub.3 -C.sub.6)cycloalkyl, or (C.sub.1 -C.sub.6)-alkyl-(C.sub.3 -C.sub.6)cycloalkyl and R.sup.4 is a group .dbd.C--N(CH.sub.3).sub.2, and m is 0, 1, 2, 3, or 4.

Abstract: Compounds of the formula ##STR1## wherein R.sub.3, R.sub.4, J, K, Z, and Het are as set forth herein are described.The compounds of formula I are useful as agents in the treatment of fungal infections.

Abstract: Disclosed herein is a process for preparing a compound of structure (I): ##STR1## which comprises cyclization of a compound of structure (II) ##STR2##

Abstract: Compounds of the following formula (I) or the formula (I).sub.p : ##STR1## wherein R.sup.1 is alkyl or alkenyl; R.sup.2 and R.sup.3 are hydrogen, alkyl, alkenyl, cycloalkyl, aralkyl, aryl, or aryl fused to cycloalkyl; R.sup.4 is hydrogen, alkyl, alkanoyl, alkenoyl, arylcarbonyl, alkoxycarbonyl, tetrahydropyranyl, tetrahydrothiopyranyl, tetrahydrothienyl, tetrahydrofuryl, a group of formula --SiR.sup.a R.sup.b R.sup.c, in which R.sup.a, R.sup.b and R.sup.c are alkyl or aryl, alkoxymethyl, (alkoxyalkoxy)methyl, haloalkoxymethyl, aralkyl, aryl or alkanoyloxymethoxycarbonyl; R.sup.5 is carboxy or --CONR.sup.8 R.sup.9, wherein R.sup.8 and R.sup.9 hydrogens or alkyl, or R.sup.8 and R.sup.9 together form alkylene; R.sup.6 is hydrogen, alkyl, alkoxy or halogen; R.sup.7 is carboxy or tetrazol-5-yl; R.sub.p.sup.1 is hydrogen, alkyl, cycloalkyl or alkanoyl; R.sub.p.sup.2 is a single bond, alkylene or alkylidene; R.sub.p.sup.3 and R.sub.p.sup.4 are each hydrogen or alkyl; R.sub.p.sup.6 is carboxy or tetrazol-5-yl; and X.

Abstract: Compounds having the formula ##STR1## and pharmaceutically acceptable salts thereof wherein a, b and d are all carbon atoms or one of a, b and d is a nitrogen atom or --N(O)-- and the others are carbon atoms; Y is a single bond, --CH.sub.2 --, --C(O)--, --O--, --S-- or --N(R.sup.8)--; and R.sup.1 to R.sup.7 are as defined herein. These compounds have potassium channel activating activity and are useful, therefore for example, as cardiovascular agents.

Abstract: This invention provides novel heterocyclic derivatives, their pharmaceutical formulations, and their use for antagonizing angiotensin II receptors in mammals.

Abstract: Disclosed are herbicidal tetrazolinone derivatives, selective in paddy fields of the formula ##STR1## wherein X represents C.sub.1-4 alkyl,n represents 1, 2, 3 or 4,R.sup.1 and R.sup.2 each independently represents C.sub.1-6 alkyl, C.sub.2-4 alkenyl, C.sub.2-6 alkynyl, C.sub.3-8 cycloalkyl, aryl which may optionally be substituted (wherein the substituent is at least one radical selected from the group consisting of halogen, C.sub.1-4 alkyl, C.sub.1-2 haloalkyl, C.sub.1-2 haloalkoxy, C.sub.1-2 haloalkylthio, acyl, nitro and cyano) or aralkyl optionally substituted by halogen orR.sup.1 and R.sup.2 form, together with the N-atom to which they are bonded, a cyclic ring which may be substituted. Also, disclosed are novel intermediates useful in the preparation of the compounds of formula (I).

Abstract: The tetrazolylphenyl pivalate of the the following general formula or a pharmaceutically acceptable salt thereof: ##STR1## wherein R.sup.1 and R.sup.2 each represents a hydrogen atom, a lower alkyl group or other substituents; an elastase-inhibitory composition, a composition for preventing and treating emphysema and a composition for preventing and treating endotoxin-induced lung disorders each comprising the foregoing tetrazolylphenyl pivalate derivative or a non-toxic or acid-addition salt thereof.

Abstract: The invention relates to the products: ##STR1## in which: R.sub.1 =alkyl, alkenyl, alkynyl, alkylthio,R.sub.2B, R.sub.3B representing:hydrogen, mercapto, formyl, acyl, carboxy nitro, cyano,--PO.sub.3 (R).sub.2, R representing hydrogen, alkyl, aryl, amino or carbamoyl,the R.sub.4B radicals; ##STR2## n=0 to 2 X'=arylR.sub.4B either represents --(CH.sub.2).sub.m1 --S(O).sub.m2 --X--R.sub.10, m1=0 to 4, m2=0 to 2either m1 is different from 0, X--R.sub.10 represents amino, or whatever m1 is, X represents a single bond or --NH--, --NH--CO--, --NH--CO--NH--,R.sub.10 =alkyl, alkenyl or aryl, or hydrogen, alkyl, alkenyl, alkynyl, acyl or amino,--S--S--R.sub.4B ', R.sub.4B ' represents R.sub.4B except for amino and alkoxy, and one of R.sub.2B and R.sub.3B represents --OR.sub.4B : ##STR3## m=0 to 2, Y.sub.B ---Y.sub.1B --B--Y.sub.2B,Y.sub.1B =aryl,B=a single bond or --CO--, --O--, --NH--CO--, --CO--NH--, --O--O--(CH.sub.2).sub.p --,p=1 to 3,Y.sub.

Abstract: There is disclosed a process for producing a 2-(tetrazol-5-yl)-4-oxo-4H-benzopyran of general formula (1): ##STR1## which comprises reacting a hydroxyacetophenone of general formula (2): ##STR2## with a tetrazole compound of general formula (3): ##STR3## in the presence of a base in a solvent composed mainly of at least one selected from hydrocarbons, halogenated hydrocarbons and alcohols, and then treating the reaction mixture under acidic conditions.

Abstract: This invention comprises a process for preparing benzopyran derivatives represented by formula (I) ##STR1## in which, R.sup.1 is C.sub.1-20 alkyl, C.sub.2-20 alkenyl, C.sub.2-20 alkynyl, or a group of structure (i), (ii) or (iii).

Abstract: Naphthalene derivatives represented by the formula (I): ##STR1## wherein the symbol ##STR2## --X-- represents --O-- or --S--, .dbd.Y-- represents .dbd.N-- or .dbd.CR.sup.5 --, R.sup.1, C.sup.2, R.sup.3, R.sup.4 and R.sup.5 represent hydrogen, halogen, alkyl and the like,R.sup.6 represents hydrogen, alkyl, aryl and the like,n represents an integer of 0 to 3, --- represents a single bond or a double bond, which are useful for reducing blood sugar and blood lipid levels are provided.

Abstract: A pharmaceutical compound of the formula ##STR1## in which m is 0, 1 or 2, n and q are each 0 or 1 to 5, and p is 0 or 1, X is --CO.sub.2 H or tetrazolyl,Y is --CH.dbd.CH--, andZ is(i) phenyl, naphthyl or thienyl, said phenyl, naphthyl and thienyl being optionally substituted,(ii) --CHR.sup.1 R.sup.2 where R.sup.1 and R.sup.2 are each phenyl, naphthyl or thienyl, said phenyl, naphthyl and thienyl being optionally substituted,(iii) .dbd.CR.sup.1 R.sup.2 where R.sup.1 and R.sup.2 are each phenyl, naphthyl or thienyl, said phenyl, naphthyl and thienyl being optionally substituted, or(iv) ##STR2## where r is 0 or 1 to 3 and the phenyl rings are optionally substituted; provided that when Z is phenyl and m is 1, p is 1; and salts and esters thereof.

Abstract: A process for preparing substituted benzopyran derivatives which comprises a final step cyclisation of the corresponding open-chain intermediates.

Abstract: Imidazole derivatives having A II antagonist activity, of Formula I, the processes for the preparation thereof, pharmaceutical compositions containing them and the use thereof as therapeutic agents. The described compounds having A II antagonist activity can be used in various cardiovascular disorders.

Abstract: A class of novel 1H-indole-3-acetic acid hydrazides is disclosed together with the use of such indole compounds for inhibiting sPLA.sub.2 mediated release of fatty acids (e.g., arachidonic acid) for treatment of conditions such as septic shock.

Abstract: Disclosed is a method for removing a protective group of an N-protected tetrazolyl compound which comprises reacting said N-protected tetrazolyl compound with a mineral acid under substantially anhydrous conditions in the presence of an alcohol, insuring a high reaction yield of the object tetrazolyl compound.

Abstract: Pharmaceutical compounds which are azolo-fused pyrimidine compounds having the formula ##STR1## in which .dbd.

Abstract: This invention provides novel heterocyclic derivatives, their pharmaceutical formulations, and their use for antagonizing angiotensin II receptors in mammals.

Abstract: Cyclohexanol esters of the formula I ##STR1## are described in which the radicals have the given meaning. The compounds are pharmacologically active and may therefore be used as pharmaceuticals, in particular for treating diabetes and other diseases which are characterized by an elevated secretion of glucose from the liver or by an elevated activity of the glucose-6-phosphatase system.

Abstract: Phenoxyphenylacetic acids and derivatives of the general structural formula I ##STR1## have endothelin antagonist activity and are useful in treating cardiovascular disorders, such as hypertension, postischemic renal failure, vasospasm, cerebral and cardiac ischemia, myocardial infarction, endotoxic shock, benign prostatic hyperplasia, inflammatory diseases including Raynaud's disease and asthma.

Abstract: This invention provides novel phenyl and heterocyclic derivatives, their pharmaceutical formulations and their use for antagonizing angiotensin II receptors in mammals.

Abstract: A compound of formula (I): ##STR1## in which: R represents naphthyl, 5,6,7,8-tetrahydronaphthyl, 1,2,3,4-tetrahydronaphthyl, thienyl, optionally substituted phenyl or (C.sub.3 -C.sub.7)cycloalkyl,n represents an integer such that 1.ltoreq.n.ltoreq.8, their enantiomers, diastereoisomers and epimers as well as their addition salts with a pharmaceutically acceptable acid or base and medicinal products containing the same are useful as antagonists of substance P.

Abstract: .delta.-Amino-.gamma.-hydroxy-.omega.-aryl-alkanoic acid amides of formula I ##STR1## and the salts thereof, have renin-inhibiting properties and can be used as antihypertensive medicinal active ingredients.

Abstract: Compounds of formula (I), and salts and prodrugs thereof, wherein Q is optionally substituted phenyl or benzhydryl; X and Y are each H or together form a group=O; Z is O, S or NR.sup.9, where R.sup.9 is H or C.sub.1-6 alkyl; R.sup.1 represents H or C.sub.1-6 alkyl; R.sup.2 represents C.sub.1-6 alkyl substituted by CONR.sup.7 (CH.sub.2).sub.p R.sup.8 (where R.sup.7 is H or C.sub.1-6 alkyl, R.sup.8 is optionally substituted heteroaryl and p is 0, 1, 2, 3, 4, 5 or 6); R.sup.3 represents H, C.sub.1-6 alkyl or C.sub.2-6 alkynyl; R.sup.4 represents H, C.sub.1-6 alkyl or optionally substitute phenyl; R.sup.5 represents optionally substituted phenyl; R.sup.6 is H or C.sub.1-6 alkyl; and q is 0, 1, 2 or 3; are tachykinin antagonists useful in therapy.

Abstract: Compounds of formula (I), wherein Q.sup.1 represents an aryl group; the dotted line represents an optional covalent bond; one of X and Y represents H and the other represents hydroxy or C.sub.1-6 alkoxy, or X and Y together form a group .dbd.O or .dbd.NOR.sup.5 where R.sup.5 is H or C.sub.1-6 alkyl; Z represents O, S or NR.sup.2, where R.sup.2 is H or C.sub.1-6 alkyl; W represents a bond or a saturated or unsaturated hydrocarbon chain of 1, 2, 3, 4, 5 or 6 carbon atoms; R.sup.1 represents H or C.sub.1-6 alkyl. R.sup.3 represents H, C.sub.1-6 alkyl or C.sub.2-6 alkenyl; R.sup.4 represents an optionally substituted phenyl group; and R.sup.6 represents a specified amino group or an optionally substituted aromatic or non-aromatic azacyclic or azabicyclic group; and salts and prodrugs are tachykinin receptor antagonists.

Abstract: Novel substituted imidazoles of Formula (I), which are useful as angiotensin II antagonists, are disclosed: ##STR1##

Abstract: A tetrazoleacetic acid derivative represented by the following general formula (I): ##STR1## .[.[in Formula (I),.]. .Iadd.wherein .Iaddend.R.sub.1 represents a hydrogen atom or an alkyl group; R.sub.2 represents a hydrogen atom, an alkyl group, an aralkyl group, a halogen atom, a haloalkyl group, a hydroxyl group, an alkoxy group, an alkoxyalkyl group, an amino group, an aryl group, an alkyl or aryl thio group, an alkyl or aryl carbonylamino group, an alkyl or aryl sulfonylamino group, an alkyl or aryl aminosulfonyl group, an alkyl or aryl sulfonyl group or an alkyl or aryl sulfinyl group; and X represents --O-- or --S--.[.].]. except for [5-(2-thienyl)tetrazol-1-yl] acetic acid, [5-(2-furyl)tetrazol-1-yl) acetic acid.Iadd., (5-(5-bromo-2-furyl)tetrazol-1-yl)acetic acid, (5-(5-phenylthio-2-furyl)tetrazol-1-yl)acetic acid, (5-(5-phenylsulfonyl-2-furyl)tetrazol-1-yl)acetic acid .Iaddend.