Abstract: Oxophthalazinyl acetic acids having benzothiazole side chains are prepared by reacting an oxophthalazinyl thioacetamide acetate with hydrogen sulfide and a nitrophenyl compound having a reactive group such that the benzothiazole side chain may be formed by ring closure involving the thiocaetamide group. The oxophthalazinyl thioacetamide may be prepared by reacting the corresponding cyanomethyloxophthalazinyl acetate with hydrogen sulfide in the presence of tertiary amines. Analogous indazole and oxopyridopyridazinone acetic acids may be prepared similarly, as well as oxophthalazinyl, indazole and oxopyridopyridazinone acetic acids having thiazolopyridinyl side chains.

Abstract: Isothiazolo-quinoline derivatives are described which are cytotoxic for various tumor cell lines and are useful in the treatment of neoplastic diseases.

Abstract: A novel series of polycyclic amines, derivatives, methods of making the compounds, novel intermediates, compositions containing them, and methods for using them in the treatment and prevention of cerebrovascular disorders are disclosed.

Abstract: 2-(1-Substituted-2-imidazolin-2-yl)benzoic and nicotinic acids, and derivatives thereof, which are effective in the control of undesirable plant species are described. Also described are a method for the herbicidal use of the compounds and a method for their preparation.

Abstract: This invention relates to a compound of the formula: ##STR1## in which R.sub.1 representsa 1,2,3,6-tetrahydro-1-pyridyl radical substituted in the 4-position.a 1-piperazinyl radical substituted in the 4-position.a piperidino radical substituted in the 4-positioneither:R.sub.2 and R.sub.3, which are identical, represent a hydrogen or halogen atom and R.sub.4 represents a hydrogen atom orR.sub.2 and R.sub.4 represent a hydrogen atom and R.sub.3 represents a halogen atom or an acetylamino radical orR.sub.2 and R.sub.3 represent a hydrogen atom and R.sub.4 represents a halogen atom and R.sub.5 represents a --CH.dbd. group.or R.sub.2, R.sub.3 and R.sub.4 represent a hydrogen atom and R.sub.5 represents a nitrogen atom.R.sub.

Abstract: Novel polycyclic pyranyl compounds, pharmaceutical compositions, and their use as anti-viral agents are disclosed.

Abstract: Isoindoline derivatives represented by the formula (I) and their salts are disclosed. ##STR1## There are many varieties for the compound depending on the types of residues R.sup.1 -R.sup.9 and X. The compounds can be prepared from quinoline derivatives of the formula (II) and an isoindoline derivatives of the formula (III). The compounds of formula (I) and their salts have excellent antibacterial activities against both gram positive and gram negative microorganisms. They can be used as a medicine, an agrichemical, and a food preservative.

Abstract: Compounds represented by the general formula: ##STR1## in which R.sub.1 and R.sub.2 are selected from hydrogen, C.sub.1 -C.sub.6 alkyl or C.sub.2 -C.sub.6 alkenyl , phenyl or benzyl or R.sub.1 and R.sub.2 form together with the nitrogen atom to which they are attached a C.sub.4 -C.sub.8 saturated heterocycle, R.sub.3 is selected from hydrogen, C.sub.1 -C.sub.6 alkyl, phenyl or C.sub.7 -C.sub.9 phenyl-alkyl, R.sub.4 is selected from hydrogen or C.sub.1 -C.sub.4 alkyl, R.sub.5 and R.sub.6 are selected from hydrogen or halogen, C.sub.1 -C.sub.3 or alkoxy, nitro or trifluoromethyl; Z is selected from OH, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.4 alkyl, benzyl, C.sub.4 -C.sub.6 aryl with or without a heteroatom, or NR.sub.8 R.sub.9, R.sub.8 and R.sub.9 being selected from hydrogen, C.sub.1 -C.sub.4 alkyl, phenyl or benzyl; R.sub.10 is selected from hydrogen, C.sub.1 -C.sub.

Abstract: Indole and indole derivatives are prepared by contacting under mild reaction conditions an N-(2-toly)formidate, N-(3-methyl-2-pyridyl)formimidate, or N-methyldiazyl formimidate with an alkali metal amide.

Abstract: There are disclosed a 9-acylamino-tetrahydroacridine derivative represented by the following formula (I): ##STR1## wherein R ##STR2## are as defined in the specification, its optical antipode or pharmaceutically acceptable acid addition salt thereof and a memory enhancing agent containing the same as an active ingredient.

Abstract: 7- or 8-Substituted, partially hydrogenated pyrazolo[3,4-g]quinoline, thiazolo[4,5-g]quinoline, oxazolo[4,5-g]quinoline, and pyrrolo[3,4-g]quinoline derivatives, and 8- or 9-substituted, partially hydrogenated pyrido[2,3-g]quinazoline derivatives are D-2 dopamine agonists. 6-Oxo-1-substituted-octahydroquinolines and 6-oxo-1-substituted-decahydroquinolines which are additionally substituted in the 3- or 4-position are intermediates useful in preparation of the dopamine agonists. Acetals of 4,6-dioxo-1-substituted-decahydroquinoline 3-carboxylic acid esters enable synthesis of the foregoing compounds.

Abstract: The present invention comprises certain quinoline lactams of formula I; pharmaceutically acceptable salts of the compounds of formula I; pharmaceutical compositions containing a compound of formula I, or a pharmaceutically acceptable salt thereof, for use in the treatment of anxiety; and processes for the manufacture of the compounds of formula I, as well as intermediates for use in such manufacture.

Abstract: A compound of the formula ##STR1## and pharmaceutically acceptable salts thereof, in which A is --N.dbd.N--NH--, --X--C(R.sub.2).dbd.N--, --N.dbd.C(R.sub.2)--X--, --X--C(R.sub.2)--CH(R.sub.2).dbd.N-- or --N.dbd.C(R.sub.2)--CH(R.sub.2)--X--, wherein X is sulphur, oxygen or nitrogen and R.sub.2 is provided that where two R.sub.2 -groups are present in the A group one of the R.sub.2 groups is hydrogen, amino, substituted amino, C.sub.1-6 alkyl, substituted acylamino or one of the following groups: ##STR2## wherein R.sub.a is hydrogen, amino, substituted amino, C.sub.1-6 alkoxy, heterocyclic five membered ring or --NHCOR', wherein R' is C.sub.1-6 alkyl, aryl or heterocyclic five membered ring, R.sub.b is hydrogen, C.sub.1-6 alkoxy, C.sub.1-6 alkylthio or hydroxy, R.sub.c is hydrogen, C.sub.1-6 alkyl or oxygen and R.sub.d is C.sub.1-6 alkyl or oxygen, R.sub.e is hydrogen, hydroxy or C.sub.1-6 alkoxy, R.sub.f is C.sub.1-6 alkyl, provided that where two R.sub.2 -groups are present in the A group, one of the R.sub.

Abstract: Oxophthalazinyl acetic acids having benzothiazole side chains are prepared by reacting an oxophthalazinyl thioacetamide acetate with hydrogen sulfide and a nitrophenyl compound having a reactive group such that the benzothiazole side chain may be formed by ring closure involving the thioacetamide group. The oxophthalazinyl thioacetamide may be prepared by reacting the corresponding cyanomethyloxophthalazinyl acetate with hydrogen sulfide in the presence of tertiary amines. Analogous indazole and oxopyridopyridazinone acetic acids may be prepared similarly, as well as oxophthalazinyl, indazole and oxopyridopyridazinone acetic acids having thiazolopyridinyl side chains.

Abstract: A benzothiazol compound having the formula is disclosed and is effective to inhibit the production of leukotriene. It is useful against allergy, asthma, affections of the skin, allergic rhinitis and affection of a cardiovascular system. ##STR1## in which R20 is ester or amide and --NR5R6 is amino in variety.

Abstract: A fogged direct positive photographic silver halide emulsion containing a sensitizing amount of at least one cyanine dye defined above, e.g., cyanine dye containing a 1-phenylindole nucleus substituted in the 2-position with the 3-pyridyl group. The said cyanine dye is also covered. The dye useful in sensitizing the silver halide emulsion useful for fogged direct-positive films.

Abstract: The invention relates to new thiazolo[4,5-c]quinoline derivatives of the general Formula I ##STR1## and acid addition salts thereof, a process for the preparation of the same and pharmaceutical compositions comprising the said compounds.The substituent definition of the general Formula I is as follows:R stands for hydrogen; a straight or branched chained alkyl group having 2-5 carbon atoms optionally substituted by one or more halogen atom(s); phenyl or phenyl-(lower alkyl) optionally bearing one or more substituent(s) on the phenyl ring;R.sup.1 and R.sup.2 are identical or different and stand for hydrogen, halogen or lower alkyl).The compounds of the general Formula I possess valuable central nervous depressive properties.

Abstract: The present invention includes compounds represented by the formula: ##STR1## wherein R.sub.1 is a hydroxy, a C.sub.1 to C.sub.6 alkoxy, benzoxy, or an alkylcarbonyloxymethoxy group, or R.sub.3 together with R.sub.1 forms a group of the formula --Y--NH-- where Y is oxygen or sulfur; or R.sub.3 is hydrogen; A is nitrogen or CR.sub.2, where R.sub.2 is hydrogen, or halogen, or R.sub.2 together with R forms a group of the formula --X--CH.sub.2 --CH(R.sub.6)-- or --X--CH.sub.2 --CH.dbd.CH.sub.2, wherein X is CH.sub.2, O, S, NH, or NCH.sub.3, and R.sub.6 is hydrogen, alkyl, or C.sub.1 -C.sub.3 haloalkyl; or R is (1) a C.sub.1 to C.sub.4 alkyl, (2) lower cycloalkyl, (3) alkylamino, (4) haloalkyl, (5) an aromatic heterocyclic ring or (6) a substituted phenyl group; and Z is a carbocyclic group;or a pharmaceutically acceptable salt thereof. The compounds of the present invention are useful as antibacterial agents.

Abstract: Aryl-substituted naphthyridines and pyridopyrazines are disclosed which are useful in treating allergic reactions, inflammation, peptic ulcers and/or hyperproliferative skin disease. Pharmaceutical compositions and methods of treatment employing such compounds are also disclosed.

Abstract: 7- or 8-Substituted, partially hydrogenated pyrazolo[3,4-g]quinoline, thiazolo[4,5-g]quinoline, oxazolo[4,5-g]quinoline, and pyrrolo[3,4-g]quinoline derivatives, and 8- or 9-substituted, partially hydrogenated pyrido[2,3-g]quinazoline derivatives are D-2 dopamine agonists. 6-Oxo-1-substituted-octahydroquinolines and 6-oxo-1-substituted-decahydroquinolines which are additionally substituted in the 3- or 4-position are intermediates useful in preparation of the dopamine agonists. Acetals of 4,6-dioxo-1-substituted-decahydroquinoline 3-carboxylic acid esters enable synthesis of the foregoing compounds.

Abstract: Novel polycyclic quinoline, naphthyridine and pyrazinopyridine derivatives are disclosed which are useful for treating allergic reactions, inflammation, peptic ulcers, hypertension, and hyperproliferative skin diseases and for suppressing the immune response in mammals. Methods for preparing said compounds are also disclosed.

Abstract: Tricyclic oxazolones enhance myocardial contractile force and are useful as cardiotonics in the treatment of heart failure.

Abstract: A compound of the formula ##STR1## wherein X is hydrogen, halogen or nitro; Ar is phenyl or naphthyridinyl which may optionally be substituted; and either one of Z.sup.1 and Z.sup.2 is hydrogen and the other is lower alkanoyloxy or hydroxy, each of Z.sup.1 and Z.sup.2 is lower alkoxy, or Z.sup.1 and Z.sup.2 combinedly represent hydroxyimino or oxo; and a salt thereof, act on the central nervous system but are weak in adverse effects such as hypnotic and muscle relaxant effects.

Abstract: 3-7-Diheterabicylo[3.3.1]nonanes and derivatives thereof are disclosed. Their method of preparation and use as antiarrhythmic agents is given.

Abstract: It has been found that 2-methyl-thiazolo[4,5-c]quinoline and pharmaceutically acceptable acid addition salts and hydrates thereof possess valuable central nervous depressive properties being different from those of benzodiazepines. The invention relates to pharmaceutical compositions comprising as active ingredient 2-methyl-thiazolo[4,5-c]quinoline of the Formula I ##STR1## or a pharmaceutically acceptable acid addition salt or hydrate thereof.

Abstract: This invention relates to novel isoxazolo-naphthyridine, isoxazolo-quinoline, isothiazolo-naphthyridine, and isothiazolo-quinoline, derivatives having antibacterial properties.

Abstract: The present invention relates to novel antibacterial agents, corresponding to the following general formula I ##STR1## in which: Q represents an aromatic ring,X represents a hydrogen atom or a linear or branched alkyl group,Y represents a linkage or an alkyl group,Z represents a hydrogen atom, an alkyl, aralkyl or heteroalkyl group.These compounds constitute anti-bacterial agents with multiple pharmacological activity.

Abstract: Hetero [f] fused carbocyclic pyridines are described, as well as methods for the preparation and pharmaceutical compositions of same, which are useful as dopamine agonists with selectivity for the presynaptic dopamine receptor and are useful as dopaminergic, antipsychotic and antihypertensive agents as well as for treating hyperprolactinaemia-related conditions and central nervous system disorders.

Abstract: Aryl-substituted naphthyridines and pyridopyrazines are disclosed which are useful in treating allergic reactions, inflammation, peptic ulcers and/or hyperproliferative skin disease. Pharmaceutical compositions and methods of treatment employing such compounds are also disclosed.

Abstract: A compound of the formula: ##STR1## (wherein R is phenyl optionally substituted by one or two members selected from the group consisting of trifluoromethyl, C.sub.1 -C.sub.5 alkyl, C.sub.1 -C.sub.5 alkoxy, C.sub.1 -C.sub.5 alkylthio, nitro, amino C.sub.1 -C.sub.5 alkanoylamino and C.sub.1 -C.sub.5 alkoxycarbonyl or 5- or 6-membered heterocyclic group optionally substituted by one or two members selected from the group consisting of halogen, C.sub.1 -C.sub.5 alkyl and C.sub.1 -C.sub.5 alkoxy,Q is hydrogen, C.sub.1 -C.sub.5 alkyl, C.sub.1 -C.sub.10 acyl, C.sub.1 -C.sub.5 alkylsulfonyl or C.sub.6 -C.sub.10 arylsulfonyl, ##STR2## R.sup.1, R.sup.2, R.sup.3, and R.sup.4 each is hydrogen, halogen C.sub.1 -C.sub.5 alkyl, C.sub.1 -C.sub.5 alkoxy or C.sub.1 -C.sub.

Abstract: Novel substituted N-[(4-piperidinyl)alkyl] bicyclic condensed oxazol- and thiazolamines useful as anti-depressives, in the treatment of Parkinson's disease and in the treatment of diseases related with disturbed enterokinesia.

Abstract: New quinoline compound, and the corresponding 1,2-; 1,3-; and 1,4-benzodiazines, the quinoline compounds being of the formula: ##STR1## and salts thereof, wherein R.sub.1 and R.sub.2 are independently hydrogen, lower alkyl, halo, trifluoromethyl, amino, lower alkyl amino, lower acylamino, cyano, aryl, aryl/lower alkylene, nitro, lower alkynyl, lower alkenyl, lower alkyl sulfinyl, lower alkyl sulfonyl, lower alkoxycarbonyl, carboxyl, lower alkoxy, lower alkanoyl, or lower alkenoyl,Y is oxygen, sulfur, nitrogen or R.sub.3 N wherein R.sub.3 is hydrogen, lower alkyl, alkenyl, alkynyl, aryl, aralkyl, acyl, aminoalkyl, or carboxyalkyl,Z is oxygen, sulfur or nitrogen,X is cyano, carbalkoxyl, carboxyl, formyloximino, tetrazolyl, carbalkoxyalkyl or carboxyalkyl, andm is 0 or 1, are useful as medicinals, especially for treatment of asthma, and/or as intermediates in the preparation of compounds useful for treating asthma.

Abstract: Trans-(.+-.)-2- and/or -5-permissibly substituted octahydro-oxazolo[4,5-g]quinolines, acid addition salts thereof and individual enantiomers thereof, useful as dopamine agonists or intermediates of the preparation of dopamine agonists.

Abstract: Substituted hexahydro arylquinolizines and pharmaceutically acceptable salts thereof are selective .alpha..sub.2 -adrenergic receptor antagonists and thereby useful as antidepressants, antihypertensives, ocular antihypertensives, antidiabetics, antiobesity and platelet aggregation inhibitors and modifiers of gastrointestinal motility.

Abstract: Substituted quinoline, [1,5]- and [1,8]-naphthyridine and pyrido[2,3-b]pyrazine derivatives are anti-allergic, anti-inflammatory and cytoprotective agents. Methods for their preparation and use are disclosed.

Abstract: Resins are obtained by Diels-Alder polymerization of a monomer of the formula ##STR1## where R is a hydrogen atom or an aryl group; andL is an aromatic linking group.

Abstract: This invention describes tricyclic derivatives which are useful as histamine H.sub.1 -antagonists. A particular compound of this invention is 3-[3-(pyrido[3,2-b][1,4]-benzothiazin-10-yl)propylamino]-4-(pyrid-4-ylmeth ylamino)-1,2,5-thiadiazole-1-oxide.

Abstract: Trans-(.+-.)-2- and/or -5-permissibly substituted octahydro-oxazolo[4,5-g]quinolines, acid addition salts thereof and individual enantiomers thereof, useful as dopamine agonists or intermediates of the preparation of dopamine agonists.

Abstract: Compounds of the formula formula IA or IB ##STR1## wherein A represents an optionally substituted saturated divalent grouping which together with the two carbon atoms to which it is attached represents a fused 5-, 6- or 7-membered carbocyclic or heterocyclic ring selected from optionally substituted fused cyclopenteno, cyclohexeno, cyclohepteno, dihydrothieno, dihydrothiopyrano, tetrahydrothiepino, dihydrofuro, dihydropyrano, tetrahydrooxepino, dihydropyrrolo, tetrahydropyrido and tetrahydroazepino; R.sub.1 represents lower alkyl, phenyl, or phenyl mono- or disubstituted by lower alkyl, lower alkoxy, halogen or trifluoromethyl; or R.sub.1 represents an aromatic heterocyclic radical selected from e.g. optionally substituted pyridyl, quinolyl, isoquinolyl, pyrimidyl and thiazolyl; R.sub.2, R.sub.3, R.sub.3 ' are hydrogen or lower alkyl; and pharmaceutically acceptable salts; are useful as benzodiazepine receptor modulators for the treatment of nervous system disorders.

Abstract: There are disclosed compounds having the formula ##STR1## wherein R.sub.1 is hydrogen, loweralkyl, arylloweralkyl, aryl or heteroaryl; R.sub.2 is hydrogen or loweralkyl; R.sub.3 is loweralkyl, loweralkoxyloweralkyl, cycloalkyl, arylloweralkyl or heteroarylmethyl; and R.sub.4 is hydrogen or loweralkyl; or a pharmaceutically acceptable acid addition salt thereof, which are useful as anxiolytic agents, methods for synthesizing them, and pharmaceutical compositions comprising an effective amount of such a compound.

Abstract: There are disclosed compounds having the formula ##STR1## wherein R.sub.1 is hydrogen, loweralkyl, arylloweralkyl, aryl or heteroaryl; R.sub.2 is hydrogen or loweralkyl; R.sub.3 is loweralkyl, loweralkoxyloweralkyl, cycloalkyl, arylloweralkyl or heteroarylmethyl; and R.sub.4 is hydrogen or loweralkyl; or a pharmaceutically acceptable acid addition salt thereof, which are useful for alleviating pain and lowering blood pressure, methods for synthesizing them, and pharmaceutical compositions comprising an effective amount of such a compound.

Abstract: The present invention relates to new N-acyl derivatives of amino acids.These derivatives correspond to the general formula I below: ##STR1## in which A represents a linear or branched, saturated hydrocarbon radical containing from 1 to 6 carbon atoms or a saturated ring containing 6 carbon atoms,X represents a --COOH radical, a --COOAlkyl radical (alkyl from C.sub.1 to C.sub.4), a hydrogen atom or a --CH.sub.3 group when Y is --COOH or --COOAlkyl,Y represents a --COOH radical, a --COOAlkyl radical (alkyl from C.sub.1 to C.sub.4), an --NH.sub.2 group, an --SH group, an --SCH.sub.3 group, a --NH--CH(.dbd.NH)--NH.sub.2 group, a substituted or unsubstituted phenyl group, an indolin-3-yl group or a 5-hydroxyindolin-3-yl group, andQ represents an optionally substituted aromatic ring or an optionally substituted heterocycle containing 1 or 2 nitrogen atoms.Drugs having an antiallergic action.

Abstract: Quinoline and substituted quinolines are prepared by reacting aniline or a substituted aniline with an .alpha., .beta.-monounsaturated aldehyde in a high-boiling mineral oil by a method in which the high-boiling mineral oil is replaced when it becomes enriched with by-products, and the said mineral oil enriched with by-products is removed.

Abstract: Compounds of the formula formula IA or IB ##STR1## wherein A represents an optionally substituted saturated divalent grouping which together with the two carbon atoms to which it is attached represents a fused 5-, 6- or 7-membered carbocyclic or heterocyclic ring selected from optionally substituted fused cyclopenteno, cyclohexeno, cyclohepteno, dihydrothieno, dihydrothiopyrano, tetrahydrothiepino, dihydrofuro, dihydropyrano, tetrahydrooxepino, dihydropyrrolo, tetrahydropyrido and tetrahydroazepino; R.sub.1 represents lower alkyl, phenyl, or phenyl mono- or disubstituted by lower alkyl, lower alkoxy, halogen or trifluoromethyl; or R.sub.1 represents an aromatic heterocyclic radical selected from e.g. optionally substituted pyridyl, quinolyl, isoquinolyl, pyrimidyl and thiazolyl; R.sub.2, R.sub.3, R.sub.3 ' are hydrogen or lower alkyl; and pharmaceutically acceptable salts; are useful as benzodiazepine receptor modulators for the treatment of nervous system disorders.

Abstract: Methine dyes are disclosed which contain a 2-halo or pseudohalo substituted 1,2,5-oxatellurazole ring fused with an aromatic nucleus, the aromatic nucleus being substituted with a methine linkage terminating in an auxochrome providing a conjugated resonance chromophore. The dyes can be formed by condensing a methine linkage precursor with a compound containing an oxatellurazole ring fused with an aromatic nucleus. The dyes are useful in optical recording elements and in photographic elements.

Abstract: Substituted 1,8-naphthyridinones are anti-allergic, anti-inflammatory and cytoprotective agents. Methods for their preparation and use are disclosed.

Abstract: Novel isoxazoloquinolinones of the formula ##STR1## wherein R is selected from the group consisting of hydrogen, fluorine, chlorine, bromine, alkyl and alkoxy of 1 to 5 carbon atoms, --NO.sub.2 and CF.sub.3 -- and R.sub.1 is phenyl optionally substituted by at least one member selected from the group consisting of halogen and alkyl and alkoxy of 1 to 5 carbon atoms having anxiolytic activity and their preparation and novel intermediates.

Abstract: (1H-Tetrazol-5-yl)tetrazolo[1,5-a]thienopyridines and related compounds which are useful as antiallergic agents are described herein. The compounds are prepared by the reaction of an appropriate halocyano-quinoline with ammonium chloride and an azide such as sodium azide in an inert solvent such as dimethylformamide.

Abstract: Compounds of the formula ##STR1## wherein A is ##STR2## and R is hydrogen, alkyl of 1 to 5 carbon atoms, alkanoyl of 1 to 5 carbon atoms, alkenyl of 3 to 5 carbon atoms, (alkoxy of 1 to 4 carbon atoms)carbonyl, or aralkyl of 7 to 11 carbon atoms optionally halo-substituted,and non-toxic, pharmacologically acceptable acid addition salts thereof. The compounds as well as their salts are useful as bradycardiacs.

Abstract: New quinoline compound, and the corresponding 1,2-; 1,3-; and 1,4-benzodiazines, the quinoline compounds being of the formulae: ##STR1## and salts thereof, wherein R is hydrogen, acyl, carboethoxy,(3-methoxyphen)acetyl,(2-phenyl)propionyl, dimethylcarbamoyl or methyl,R.sub.1 and R.sub.2 are independently hydrogen, lower alkyl, halo, trifluoromethyl, amino, lower alkyl amino, lower acylamino, cyano, aryl, aryl/lower alkylene, nitro, lower alkynyl, lower alkenyl, lower alkyl sulfinyl, lower alkyl sulfonyl, lower alkoxycarbonyl, carboxyl, lower alkoxy, lower alkanoyl, or lower alkenoyl,Y is oxygen, sulfur, nitrogen or R.sub.3 N wherein R.sub.