Abstract: This invention relates to a selective process for preparing bicyclic lactam-lactone compounds wherein the rings are fused, i.e. the rings share at least two carbon atoms, or are isolated. In particular, the present invention provides a process for selectively reacting novel 1-hydrocarbylamino (or heteroatom-substituted hydrocarbylamino); 1,1-dicarboxylic acid, alkylesters; 1-alkanolactonyl or hydrocarbyl (or heteroatom-substituted hydrocarbyl) alkanonylactonyl methane, as the salt of an acid having a pKa of 0 or more, to provide bicyclic lactam-lactone compounds. The selectively of the reaction to either fused or isolated bicyclic compounds is controlled by cyclizing the novel salts, in the absence of a base, a cyclizing said novel salts, in the presence of an amount of base substantially equivalent to said acid, respectively.

Abstract: The compound of the formula ##STR1## wherein X is a cyclic group which may optionally be substituted; Y is a carboxyl group which may optionally be esterified or amidated; Z is --CH.dbd.CH--CH.dbd.CH--, --S--(CH.sub.2).sub.l --S-- is an integer of 1 to 3), --N.dbd.CH--CH.dbd.N-- or --(CH.sub.2).sub.m --(m is an integer of 3 to 5); ring A may optionally be substituted with halogen, nitro, amino, alkanoylamino, alkoxycarbonyl, carboxyl or carbamoyl; and n is an integer of 1 to 3, and salts thereof. The compounds display a strong antianxiety effect to mammalian animals and are useful for the prevention or treatment of a disease such as psychoromatic disease and anxiety neurosis.

Abstract: Purified Clausenamide of the formula ##STR1## is obtained by extraction of leaves of Clausena lansium followed by purification, Reduction products, ethers, etc. can be produced. The compounds are effective in treating hypoxia and amnesia.

Abstract: 5-Aroyl-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole-1,1-dicarboxylates of the formula ##STR1## are prepared from 2-halopyrroles. Hydrolysis and .beta.-decarboxylation of these compounds affords ketorolac and related compounds.

Abstract: A compound of formula (I) or a pharmaceutically acceptable salt thereof: ##STR1## in which A represents a bond or --CH.sub.2 -- and B represents hydrogen, or A and B together with the carbon atom to which they are both attached represents a group ##STR2## R represents R.sub.1 OOC-- in which R.sub.1 is C.sub.1-4 alkyl, C.sub.2-4 alkenyl or C.sub.2-4 alkynyl; R.sub.2 O-- in which R.sub.2 is C.sub.1-3 alkyl, C.sub.1-2 alkylcarbonyl or aminocarbonyl optionally substituted by one or two methyl groups; or R.sub.3 CH.sub.2 - in which R.sub.3 is C.sub.1-2 alkoxy; and p represents an integer of 2 to 4, and wherein compounds of formula (I) where B is hydrogen have the stereochemical configuration in which the group R and the methylene bridge are both on the same side of the plane of the molecule which contains both bridge head atoms and the ring carbon atom bonded to the group R.

Abstract: 2,3-Dihydro-1H-pyrrolo[1,2-a]pyrrole-1,7-dicarboxylate intermediates of the formula, ##STR1## in which each R is independently H or lower alkyl,are prepared from di(lower alkyl) 1,3-acetonedicarboxylates.

Abstract: 1-Phenyl-3-azabicyclo[3.1.0]hexane-2,4-diones of the formula ##STR1## wherein R.sub.1 is hydrogen, R.sub.2 is hydrogen, sulfo or acyl and R.sub.3 is hydrogen, or R.sub.1 is a saturated or unsaturated aliphatic, cycloaliphatic or cycloaliphatic-aliphatic carbon radical of up to and including 18, preferably of up to and including 12, carbon atoms, R.sub.2 is hydrogen, lower alkyl, sulfo or acyl and R.sub.3 is hydrogen or lower alkyl, and to salts thereof, and salts thereof, have valuable pharmacological properties and are effective aromatase inhibitors. They can therefore be used for the treatment of hormonal diseases, in particular mammary carcinomas.

Abstract: 2,3-Dihydro-1H-pyrrolo[1,2-a]pyrrole-1,7-dicarboxylates of the formula, ##STR1## in which each R is independently H or lower alkyl, are prepared from di(lower alkyl) 1,3-acetone-dicarboxylates.

Abstract: A substance SS42227 represented by the following formula (I): ##STR1## in which X represents >CH.sub.2 or >C=CHOH. The substance has antimicrobial and antitumor activities, and thus is useful as a medicine.

Abstract: A novel pyrrolizidine compound of the formula ##STR1## wherein R.sup.1 is an alkyl group of 1 to 4 carbon atoms or a phenyl group; and R.sup.2 and R.sup.3 are such that at least one of them is an alkyl group of 1 to 4 carbon atoms and the other, if not alkyl, being a hydrogen atom is produced by reacting .DELTA..sup.4(8) -dehydropyrrolizidine with a substituted malonic acid and the thus formed 2-substituted-8-pyrrolizidineacetic acid with a substituted aniline. The products are subjected to optical resolution and are potentantiarrhythmic agents.

Abstract: Carbocyclic and heterocyclic carbonylmethylene- and carbonylmethylpiperidines and -pyrrolidines are serotonin antagonists.

Abstract: Process for the preparation of brominated pyrrolo-[3,4-c]pyrrole pigments by bromination of a pyrrolo-[3,4-c]-pyrrole or of a mixture of different pyrrolo-[3,4-c]-pyrroles of the formula I ##STR1## with an amount of a brominating agent which supplies 0.5 to 70 equivalents of bromine, with or without a solvent, and subsequent isolation of the brominated pyrrolo-[3,4-c]-pyrrole by removal of the excess brominating agent and, if appropriate, the solvent by customary methods.The desired brominated pyrrolo-[3,4-c]pyrroles are obtained directly in a high yield by this process.Reference is made to claim 1 in respect of the meaning of substituents A, B and Z.

Abstract: Solid solutions of pyrrolo-[3,4-c]-pyrroles and quinacridones which contain(a) at least one compound of the formulae ##STR1## in which A and B are independently of each other one of the groups of the formulae ##STR2## in which R.sub.1 and R.sub.2 are independently of each other hydrogen, halogen, C.sub.1 -C.sub.5 -alkyl, C.sub.1 -C.sub.5 -alkoxy, --SR.sub.3, --N(R.sub.3).sub.2 --CF.sub.3, --CN or a group of the formulae ##STR3## R.sub.3 is C.sub.1 -C.sub.5 -alkyl and R.sub.4 and R.sub.5 are independently of each other hydrogen, halogen, C.sub.1 -C.sub.5 -alkyl, C.sub.1 -C hd 5-alkoxy, --SR.sub.3 or --CN, and(b) at least one linear quinacridone compound of the formulae ##STR4## in which W, X, Y and Z are independently of one another halogen, C.sub.1 -C.sub.5 -alkyl, C.sub.1 -C.sub.5 -alkoxy and i, k, m and n is zero, 1 or 2, the X-ray diffraction diagrams of the solid solutions differing from the sum of the X-ray diffraction diagrams of the individual components.

Abstract: A process for the preparation and conditioning of organic pigments, which comprises the use of at least one tricyclodecane alcohol or tricyclodecene alcohol.

Abstract: Hexahydropyrrolizines of the formula (I): ##STR1## wherein A is a 3-7 carbon or hetero-containing ring,R.sup.1 is a substituent, andx is 0-3.Also, pharmaceutical compositions for treating pain and methods for synthesis and use as well as novel intermediates in the synthesis.

Abstract: Nitrofuran derivatives of formula (I) ##STR1## in which n is 0 or 1 and R is a selected heterocyclic radical have useful antibacterial, antiparasitic and antifungal activity.

Abstract: Compositions comprising(a) a pyrrolopyrrole of formula I ##STR1## wherein A and B are identical or different alkyl, aralkyl, aryl or heterocyclic aromatic radicals, R.sub.1 and R.sub.2 are hydrogen atoms, unsubstituted or substituted alkyl radicals, and also alkenyl, alkynyl, aralkyl, cycloalkyl, carbamoyl, alkylcarbamoyl, arylcarbamoyl, alkoxycarbonyl, aryl, alkanoyl or aroyl groups, and X is an --O-- or --S-- atom, and(b) a pyrrolopyrrole of the above formula I that contains at least one group of formula --SO.sub.3 L, --CO.sub.2 L, --PO.sub.3 (L).sub.2, --N(R.sub.4)(R.sub.5 ), ##STR2## oder --NHCOR wherein L is --H, a group of formula M.sub.n.sup.+n or N.sup.+ H(R.sub.3)(R.sub.4)(R.sub.5), M is a monovalent, divalent or trivalent metal cation, n is 1, 2 or 3, R.sub.3 R.sub.4 and R.sub.5 are each independently --H or alkyl, aralkyl, C.sub.5 -C.sub.6 cycloalkyl or aryl radicals, or R.sub.4 and R.sub.

Abstract: The compound of the formula ##STR1## wherein X is a cyclic group which may optionally be substituted; Y is a carboxyl group which may optionally be esterified or amidated; Z is --CH.dbd.CH--CH.dbd.CH--, --S--(CH.sub.2).sub.l --S-- (l is an integer of 1 to 3), --N.dbd.CH--CH.dbd.N-- or --(CH.sub.2).sub.m -- (m is an integer of 3 to 5); ring A may optionally be substituted with halogen, nitro, amino, alkanoylamino, alkoxycarbonyl, carboxyl or carbamoyl; and n is an integer of 1 to 3, and salts thereof. The compounds display a strong antianxiety effect to mammalian animals and are useful for the prevention or treatment of a disease such as psychoromatic disease and anxiety neurosis.

Abstract: A solid solution of 1,4-diketopyrrolo-[3,4-c]-pyrrols consisting of two different compounds of the formulae ##STR1## the formulae ##STR2## or the formulae ##STR3## wherein A is one of the groups ##STR4## and B, E and D are each independently a group ##STR5## where R.sub.1 and R.sub.2 are each independently hydrogen, halogen, C.sub.1 -C.sub.5 -alkyl, C.sub.1 -C.sub.5 -alkoxy, --SR.sub.3, --N(R.sub.3).sub.2,--CF.sub.3,--CN, a group ##STR6## R.sub.3 is C.sub.1 -C.sub.5 -alkyl and R.sub.4 and R.sub.5 are each independently hydrogen, halogen, C.sub.1 -C.sub.5 -alkyl, C.sub.1 -C.sub.5 -alkoxy,--SR.sub.3 or--CN having X-ray diffraction patterns which differ from the sum of the X-ray diffraction patterns of the individual components.Such solid solutions are excellently suited as pigments for the coloration of high molecular organic material.

Abstract: The invention relates to a process for the preparation of pyrrolo[3,4-c]pyrroles of formula (1) ##STR1## wherein each of R.sub.1 and R.sub.2 independently of the other is an alkyl or aralkyl group or an isocyclic or heterocyclic aromatic radical, which process comprises reacting an ester of formula (2) or (3) ##STR2## with a nitrile of the formula R.sub.2 CN, in which formulae each of R and R' independently of the other is an alkyl or aryl group, and R.sub.1 and R.sub.2 are as defined above, in the presence of a strong base in an organic solvent.The invention also relates to compounds of formula (8) ##STR3## wherein R.sub.3 is an alkyl or aralkyl group or an ortho-substituted isocyclic or heterocyclic aromatic radical and R.sub.4 is an alkyl or aralkyl group or an isocyclic or heterocyclic aromatic radical.The pyrrolopyrroles obtained are valuable pigments for coloring compounds of high molecular weight such as plastics and lacquers in yellow to red shades of excellent fastness properties.

Abstract: There is described the use of pyrrothine derivatives of the general formula I ##STR1## wherein R.sub.1 and R.sub.3 signify hydrogen or methyl, R.sub.2 hydrogen, methyl or an acyl group with 1 to 5 carbon atoms and X and Y signify hydrogen, an equivalent of a physiolgically acceptable cation or together a single bond, for the inhibition of the allergen-induced degranulation of peripheral leukocytes.

Abstract: Compounds of formula (1) ##STR1## wherein A and B are identical or different alkyl, aralkyl or cycloalkyl groups or carbocyclic or heterocyclic aromatic radicals, R.sub.1 and R.sub.2 are hydrogen atoms or substituents which do not impart solubility in water, are particularly suitable as photoconductive substances.

Abstract: Thieno[2,3-b]pyrrole-5-sulfonamides are carbonic anhydrase inhibitors useful in the treatment of elevated intraocular pressure and glaucoma.

Abstract: A novel pyrrolizidine derivative of the formula, ##STR1## which has potent antiarrhythmic activity and low toxicity is produced. The derivative can be synthesized: by acylating 2,6-xylidine to protect the amino group, nitrating the protected xylidine to introduce a nitro group at 3-position, reducing the nitro group to an amino group, followed by diazotizing and hydrolyzing, and then the resulted 3-hydroxy-2,6-dimethylaniline being condensed with 8-halocarbonylmethylpyrrolizidine; or by nitrating N-(2',6'-dimethyl)phenyl-8-pyrrolizidineacetamide to introduce a nitro group at 3'-position, reducing the nitro group to amino group, diazotizing the amino group and hydrolyzing the diazonium compound.

Abstract: Acetylenes of the following formula (I): ##STR1## wherein Y, m, R.sup.1, R.sup.2, R.sup.3, n and R.sup.4 are defined herein and R.sup.5 is hydrogen, alkyl, cycloalkyl or substituted alkyl are useful vasodilators and antihypertensives.

Abstract: A process for the preparation of alkali metal tertiary alcoholates by reacting an alkali metal with a tertiary alcohol, which process comprises adding the hot alcohol, with stirring, to the melted alkali metal. Said process has the advantage that no inert solvents are required.

Abstract: The invention relates to pyrrolinones of formula (1) ##STR1## wherein R.sub.1 is an alkyl group containing at least 2 carbon atoms, an aralkyl group, an isocyclic or heterocyclic aromatic radical and R is an alkyl or aryl group.The invention also relates to aminodicarboxylates of formula (2) ##STR2## wherein R.sub.1 is as defined in claim 1 and R and R' are the same or different and are alkyl or aryl.The aminodicarboxylates of formula (2) are prepared by condensing a disuccinate of the formulaR'OOCCH.sub.2 CH.sub.2 COORwith a nitrile of the formula R.sub.1 CN, in the presence of a strong base and zinc chloride.The pyrrolinones of formula (1) are obtained by reacting the aminodicarboxylates of formula (2) in the presence of a strong base in an organic solvent.The compounds of formulae (1) and (2) are valuable intermediates for pigments.

Abstract: Novel bis-aminopyridinium salts are useful as phase transfer catalysts in the preparation of aromatic ethers by the reaction of hydroxyaromatic compound alkali metal salts (e.g., bisphenol A disodium salt) with activated halo- or nitro-substituted aromatic compounds (e.g., 4-nitro-N-methylphthalimide). The bis-aminopyridinium salts may be prepared by the reaction of aminopyridines with bis-carbonium ion-generating compounds such as dibromoalkanes.

Abstract: Novel 2-oxopyrrolidine compounds represented by the formula ##STR1## wherein R.sup.1 and R.sup.2 are hydrogen or alkyl group, respectively, A is alkylene group or phenyl substituted alkylene group, and B is alkylene group,or a salt thereof, a process for the preparation thereof, and a pharmaceutical agent comprising the compound or salt as an effective component.

Abstract: Novel derivatives of substituted pyrrolizine diones, isomers, and pharmaceutically acceptable derivatives thereof, have therapeutic utility for reducing amnesia induced by electroconvulsive shock and for treating senility.

Abstract: Compounds of the formula ##STR1## in which R.sub.1 and R.sub.2 are unsubstituted or substituted phenyl or naphthyl, and R.sub.3 and R.sub.4 are alkyl, alkoxycarbonyl, phenyl, benzoyl or benszl, are suitable for dyeing high molecular weight organic material.

Abstract: Electrically conductive polymers derived from heterocyclic polycyclic monomers formed of at least two cycles of five condensed members, each cycle containing one heteroatom, as well as a method of electrochemical polymerization by anodic oxidation of these monomers. These polymers may become part of composite electroconductive material.

Abstract: Dihydro-1H-pyrrolizine-3,5-(2H,6H)-dione is produced in higher overall yield in a process which comprises catalytically hydrogenating a lower alkyl ester of 4-(hydroxyimino)heptanedioic acid in the presence of a tri-(lower alkyl)amine, followed by cyclization of the product thus produced in the presence of a cyclizing agent such as acetic anhydride.

Abstract: New interphenylene prostaglandin (PGH) analogs are prepared by a method which involves reacting a bicyclic olefin, an acetylene compound and a benzylic halide together, in the presence of a palladium(O) catalyst in a single-step synthesis. By this technique a large number of new interphenylene PGH analogs can be prepared, which are useful as inhibitors of arachidonic acid induced platelet aggregation.

Abstract: 6-[2-(Substituted-pyrrol-1-yl)alkyl]pyran-2-ones and the corresponding ring-opened hydroxy-acids derived therefrom are potent inhibitors of the enzyme 3-hydroxy-3-methylglutarylcoenzyme A reductase (HMG-CoA reductase), and are thus useful hypolipidemic and hypocholesterolemic agents. Pharmaceutical compositions containing such compounds, and a method of treatment employing such pharmaceutical compositions are also disclosed.

Abstract: A unique series of N,N-dialkylaminoalkyl-hexahydro-5-oxo-1H-pyrrolizine-3-carboxamides are disclosed. These compounds are useful as agents for the reversal of amnesia. Intermediates for preparing the compounds, pharmaceutical compositions containing them, and methods for using the pharmaceutical compositions for treating senility and for the reversal of amnesia are described.

Abstract: Racemic mixture of derivatives of 5-(1-methyl-5-methylthiopyrrol-2-oyl)-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole -2-carboxylic acid and analogs were resolved into pure l- or d-isomers via concomitant isomerization and functional crystallization.

Abstract: Novel 8-substituted pyrrolizidines and quaternary ammonium salts thereof of the formula ##STR1## wherein R is a C.sub.4`-C.sub.10 alkyl, aralkyl or aryl group; a lower alkoxycarbonyl or a lower alkoxycarbonylmethyl group; a lower aliphatic carboxyl group amidated with pyridinylamine, aniline, cyclohexylamine, phenylbenzylamine or methoxyphenylbenzylamine; a lower hydroxyalkyl group which has one or two phenyl, a trihalomethylphenyl or a halophenyl group; a lower alkyl group which has a hydroxyl group esterified with acetic, benzoic, cinnamic, xanthene-carboxylic or methoxybenzoic acid, or etherified with a C.sub.2 -C.sub.

Abstract: A new group of cyanine and merocyanine spectral sensitizing dyes based on derivatives of 3-indolizine carboxaldehyde is particularly useful in sensitizing a direct positive silver halide emulsion to orange and red.

Abstract: A process for the preparation of 1,4-diketopyrrolo-[3,4-c]pyrroles of the formula ##STR1## wherein each of R.sub.1 and R.sub.2 independently of the other is an isocyclic aromatic or non-basic heterocyclic aromatic radical, which process comprises reacting 1 mole of the compound of formula ##STR2## wherein M is a metal atom, Z is alkyl or aryl, X is halogen or acetate, and m is a value from 0 to 2, with 1 mole of a compound of the formulaYCH.sub.2 COOZ (III)wherein Y is halogen, and with 1 mole of a nitrile of the formulaR.sub.1 --CN (IV) or R.sub.2 --CN (V)in an organic solvent and at elevated temperature, and isolating the compound of formula I.The compounds obtained according to the invention are suitable for pigmenting organic material of high molecular weight.

Abstract: Novel 5-aroyl-6-methylthio-, 6-methylsulfinyl-, or 6-methylsulfonyl-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acids represented by the formulas ##STR1## and the pharmaceutically acceptable, non-toxic esters and salts thereof, whereinR.sub.1 is lower alkylthio, lower alkylsulfinyl, or lower alkylsulfonyl;R.sub.2 is hydrogen, hydroxy, lower alkyl, vinyl, cyclohexyl, cyclopropyl, lower alkoxy, fluoro, chloro, bromo, trifluoromethyl, trifluoromethoxy, nitro, amino, lower alkylcarbonylamino, lower alkylthio, lower alkylsulfonyl, or lower alkylsulfinyl;X is oxygen, sulfur, N--R.sub.3 where R.sub.3 is hydrogen or lower alkyl.This invention describes intermediates of the process and the process for the production of these compounds and their pharmaceutically acceptable non-toxic salts and pharmaceutical composition thereof. The claimed compounds are useful as anti-inflammatories and analgesics in mammals.

Abstract: New thieno[2,3-b] pyrrole compounds of the formula: ##STR1## in which: R.sub.1 is hydrogen or lower alkyl,R.sub.2 is cyano, carboxy, COOM in which M is alkali alkaline-earth metal, ammonium mono-, di-, or tri-, (C.sub.1 -C.sub.5) alkylammonium optionally substituted by hydroxy, COOR in which R is lower alkyl, or ##STR2## in which R' and R" are hydrogen or lower alkyl; R.sub.3 is lower alkyl; andR.sub.4 is lower alkyl, phenyl, halophenyl, lower alkylphenyl, lower alkoxy-phenyl nitrophenyl and di-lower-alkylamino,and enatiomers thereof.These new compounds may be used as medicines especially in the treatment of acute and chronic pains.

Abstract: A novel 1-substituted pyrrolizidine derivative having the formula: ##STR1## (wherein R.sup.1 is hydrogen or a lower alkyl group; R.sup.2 is hydrogen, a lower alkyl or lower alkoxy group, or a halogen; R.sup.3 is hydrogen, a lower alkyl, lower alkoxy or amino group, or a halogen),which can be produced by reacting 1-chlorocarbonyl (or alkoxycarbonyl)pyrrolizidine with a corresponding substituted aniline (or an alkali metal salt thereof). The pyrrolizidine derivative has antiarrhythmic activity.

Abstract: The invention relates to pyrrolidinones of the general formula: ##STR1## in which: R.sub.1 represents hydrogen or alkylR.sub.2 represents alkyl, phenyl or trimethylsilyl.R.sub.3 represents 2-thienyl or a phenyl possibly substituted once or twice with halogen, methyl, methoxy or a trifluoromethyl group. It relates also to a process for the production of these compounds and to the pharmaceutical compositions containing them.

Abstract: Novel tetrazolyl- and carboxamidotetrazolyl-substituted 4H-furo[3,2-b] indoles are useful for treating allergies or for treating or ameliorating postmyocardial infarct tissue damage. Also disclosed are methods for preparing said indoles, pharmaceutical compositions containing said indoles and methods for using said pharmaceutical compositions.

Abstract: A perfluorobicyclo compound of the general formula: ##STR1## wherein either or both of Ring A and Ring B may optionally be substituted with lower perfluoroalkyl group (s) and m and n each represent 3 or 4.

Abstract: 4-Substituted proline derivatives having the formula ##STR1## can be prepared by reacting the compound having the formula ##STR2## with a compound having the formula ##STR3## to obtain a compound having the formula ##STR4## (a novel intermediate), alkylating that compound to obtain a compound having the formula ##STR5## (a novel intermediate), converting that compound to a compound having the formula ##STR6## (a novel intermediate), and oxidizing that compound to yield the desired proline having the formula ##STR7## wherein R.sub.1 is alkyl, cycloalkyl, aryl or arylalkyl, R.sub.1 ' is alkyl, cycloalkenyl, aryl or arylalkyl, R.sub.2 is alkyl, aryl, arylalkyl or cycloalkyl and R.sub.3 is hydrogen, alkyl, aryl, arylalkyl or cycloalkyl.

Abstract: Compounds of the formula ##STR1## in which R.sub.1 and R.sub.2 are unsubstituted or substituted phenyl or naphthyl, and R.sub.3 and R.sub.4 are alkyl, alkoxycarbonyl, phenyl, benzoyl or benzyl, are suitable for dyeing high molecular weight organic material.

Abstract: The present invention provides certain 2,3-didehydro-5-oxopyrrolizidinones and indolizidinones which are useful as lipid-altering and anti-atherosclerotic agents.

Abstract: A process for the preparation of 1,4-diketopyrrolo-[3,4-c]pyrroles of the formula ##STR1## wherein each of R.sub.1 and R.sub.2 independently of the other is an isocyclic or heterocyclic aromatic radical, which process comprises reacting 1 mole of a disuccinate with 2 moles of a nitrile of the formulaR.sub.1 --CN (II)orR.sub.2 --CN (III)or with 1 mole of a nitrile of the formula (II) and 1 mole of the nitrile of the formula (III), in an organic solvent and in the presence of a strong base at elevated temperature, and obtaining the compound of formula I from the reaction product by hydrolysis.The pyrrolo-[3,4-c]pyrroles are suitable for pigmenting organic material of high molecular weight.