Abstract: The invention relates to the preparation of pyrocarbonic acid diesters by an improved process and to the novel pyrocarbonic acid diesters prepared according to said process as well as to the use thereof. The core of the invention is a process for the preparation of a pyrocarbonic acid diester of formula (I) wherein R1 and R1′ are each independently of the other branched or straight-chain C1-C24alkyl, C3-C24alkenyl, C3-C24alkynyl, C4-C12cycloalkyl, C4-C12cycloalkenyl or C7-C24aralkyl, each of which is unsubstituted or substituted by one or more than one substituent which is inert under the reaction conditions, by reacting at least one ester carbonate of formula (II) with 40-50 mol % of a sulfochloride of formula (IV) in the presence of 0.

Abstract: A new beta quinacridone pigment characterized by masstone and tint reflection spectra, and a process for its preparation is disclosed. The new beta quinacridone pigment is especially useful for coloring coating compositions, such as automotive paints, and plastics. Also disclosed is a new pigment composition consisting of the inventive beta quinacridone pigment and a carbazole dioxazine pigment.

Abstract: This invention relates to a continuous process for the preparation of quinacridone pigments by(a) preparing a reaction mixture by mixing(i) a 2,5-dianilinoterephthalic acid or ester thereof, and(ii) at least about 0.5 parts by weight, per part of component (a)(i), of a dehydrating agent;(b) passing the reaction mixture through a continuous reactor having one or more heated zones at a temperature of about 80.degree. C. to about 300.degree. C. to form a crude quinacridone composition; and(c) mixing a continuous stream of the crude quinacridone composition with a liquid in which the quinacridone pigment is substantially insoluble at a ratio of about 0.5 to about 15 parts by weight of the liquid per part by weight of the crude quinacridone composition.

Abstract: Compounds of formulaA(B).sub.x (I),wherein x is an integer from 1 to 4,A is the radical of a chromophore of the quinacridone, anthraquinone, perylene, indigo, quinophthalone, isoindolinone, isoindoline, dioxazine, phthalocyanine, diketopyrrolopyrrole or azo series, which radical A contains x N-atoms linked with B, preferably with at least one immediately adjacent or conjugated carbonyl group.B is a group of formula ##STR1## and, if x=2, 3 or 4, can also be one, two or three hydrogen atom(s), and wherein Q is a group of formula ##STR2## These soluble chromophores can be readily converted to the corresponding pigments by heating, even in the substrate into which they can be incorporated without any difficulty in dissolved form.R.sub.1 -R.sub.9 are as defined herein.

Abstract: This invention relates to a process for the preparation of quinacridone pigments by(a) exposing a reaction mixture containing(i) 2,5-dianilinoterephthalic acid, 2,5-dianilino-3,6-dihydroterephthalic acid, 2,5-dianilino-3,6-dioxo-1,4-cyclohexadiene-1,4-dicarboxylic acid, and/or derivatives thereof,(ii) about 3 to about 20 parts by weight, per part of component (a)(i), of a dehydrating agent, and(iii) 0 to about 20 parts by weight, per part of component (a)(i), of a pigment additive,to microwave radiation under conditions that raise the bulk temperature of the reaction mixture to no more than about 250.degree. C.

Abstract: Solid solutions comprising quinacridone and 6,13-dihydroquinacridone are prepared by oxidation of a finely divided 6,13-dihydroquinacridone salt in an aqueous basic alcoholic medium using hydrogen peroxide as the oxidant. The solid solutions are useful as red organic high performance pigments.

Abstract: Compounds of formulaA(B).sub.x, (I),wherein x is an integer from 1 to 4,A is the radical of a chromophore of the quinacridone, anthraquinone, perylene, indigo, quinophthalone, isoindolinone, isoindoline, dioxazine, phthalocyanine or azo series, which radical contains x N-atoms attached to B, preferably with at least one directly adjacent or conjugated carbonyl group,B is a group of formula ##STR1## and, if x is 2, 3 or 4, may also be one, two or three hydrogen atoms. The symbols Q, R.sub.1, R.sub.2, R.sub.3, R.sub.4, X, Y, Z, m and n, are as defined in claim 1.These carbamate group-containing soluble chromophores are distinguished by outstanding solid state fluorescence in the UV range as well as the by ease with which they can be converted to the corresponding pigments in the substrate in which they are incorporated.

Abstract: Mixed crystal pigments of the quinacridone series New quinacridone mixed crystal pigments consisting ofa) from 85 to 99% by weight of unsubstituted .beta.-phase quinacridone of the formula (I) ##STR1## in which R.sup.1 and R.sup.2 are hydrogen atoms and b) from 1 to 15% by weight of one or more substituted quinacridones of the formula (I) in which the substituents R.sup.1 and R.sup.2 are identical or different and are chlorine, bromine or fluorine atoms or C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or carboxamido groups which can be substituted by C.sub.1 -C.sub.6 -alkyl groups, and R.sup.1 may additionally be hydrogen, are valuable quinacridones in the red-violet range.

Abstract: This invention relates to a process for preparing pigment compositions by(a) treating an organic pigment with(1) a sterically hindered and/or bulky primary amine, and(2) a liquid in which the organic pigment is insoluble, and(b) blending the resultant surface-treated pigment composition from step (a) with a pigment derivative of formula (I) ##STR1## wherein Q represents an organic pigment moiety,X is O, S, NR.sup.1, --SO.sub.2 --, --CO--, --Alk--, --Ar--, or combinations thereof,Y is --OR.sup.2, --NR.sup.3 R.sup.4, or Het,Alk is C.sub.1 -C.sub.5 alkylene, C.sub.2 -C.sub.5 alkenylene, or C.sub.4 -C.sub.5 alkadienylene, or substituted derivatives thereof,Ar is arylene,R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are independently hydrogen, C.sub.1 -C.sub.6 alkyl, C.sub.5 -C.sub.7 cycloalkyl, C.sub.7 -C.sub.16 aralkyl, or C.sub.6 -C.sub.10 aryl,Het is a heterocycle, andn is 1 to 4.

Abstract: Disclosed are aromatic condensation compounds useful as building blocks for construction of various types of optically active substances and reagent, wherein the aromatic condensation compounds are represented by general formula (1) below and capable of forming enantiomeric isomers. In the formula, two Rs are the same or different functional groups and selected from among linear, branched and cyclic hydrocarbon groups of 1-16 carbon atoms, either of which R may be hydrogen. A portion of the aromatic nucleus may be reduced, or at least one of the two nitrogen atoms may be quaternary. The aromatic condensation compounds can be produced by heating and reacting N,N'-diphenyl-p-phenylenediamine with a carboxylic acid represented by the general formula --RCOOH in an amount of at least 2 molar equivalents with respect to the diamine, at 180-210.degree. C. in the presence of a Lewis acid such as zinc chloride.

Abstract: A process for preparing transparent, pigmentary quinacridone compounds and solid solutions thereof comprises combining a premilled, sub-pigmentary powder containing at least one unsubstituted or substituted quinacridone or a derivative thereof with a sufficient amount of moderately concentrated sulfuric acid to form a slurry, then agitating this slurry in the presence of an organic liquid which is immiscible or only partially miscible with the slurry and which is effective in deagreggating and improving the crystallinity of the pigment, for an effective length of time to convert the sub-pigmentary unsubstituted or substituted quinacridone or solid solution thereof to a transparent, pigmentary form.

Abstract: Compounds of formulaA(B).sub.x, (I),wherein x is an integer from 1 to 4,A is the radical of a chromophore of the quinacridone, anthraquinone, perylene, indigo, quinophthalone, isoindolinone, isoindoline, dioxazine, phthalocyanine or azo series, which radical contains x N-atoms attached to B, preferably with at least one directly adjacent or conjugated carbonyl group,B is a group of formula ##STR1## and, if x is 2, 3 or 4, may also be one, two or three hydrogen atoms. The symbols Q, R.sub.1, R.sub.2, R.sub.3, R.sub.4, X, Y, Z, m and n, are as defined in claim 1.These carbamate group-containing soluble chromophores are distinguished by outstanding solid state fluorescence in the UV range as well as the by ease with which they can be converted to the corresponding pigments in the substrate in which they are incorporated.

Abstract: This invention relates to quinacridone pigments of formula (I) ##STR1## wherein X is O, S, or NR;R is hydrogen, C.sub.1 -C.sub.6 alkyl, C.sub.5 -C.sub.7 cycloalkyl, or C.sub.7 -C.sub.16 aralkyl;Y is C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, or halogen;the dashed line represents an optional double bond;R.sup.1 and R.sup.2 are independently hydrogen, C.sub.1 -C.sub.6 alkyl, C.sub.5 -C.sub.7 cycloalkyl, C.sub.6 -C.sub.10 aryl, C.sub.7 -C.sub.16 aralkyl, nitrile, or carboxyl or an ester or an amide thereof, or R.sup.1 and R.sup.2 together form a C.sub.5 -C.sub.8 cycloaliphatic ring or a fused-on aromatic or heteroaromatic ring;R.sup.3 is hydrogen or C.sub.1 -C.sub.6 alkyl; andm is 0, 1, or 2.This invention further relates to the preparation and use of such quinacridone pigments.

Abstract: The present invention provides novel tetrahydro-beta-carboline compounds having useful central nervous system activity. Further, there is provided tetrahydro-beta-carboline related compounds which are useful intermediates and have beneficial central nervous system activity. The invention provides formulations and methods for using the novel tetrahydro-beta-carboline and related compounds. Such compounds are particularly useful for the modulation of a 5-HT.sub.2B receptor.

Abstract: A novel 4-acylaminopyridine derivative represented by the following formula (I) is disclosed. ##STR1## The 4-acylaminopyridine derivative of the present invention is useful as a medicine for treating disturbances of memory such as senile dementia and Alzheimer's disease, since it has an action of directly activating malfunctioned cholinergic neuron.

Abstract: The present invention provides novel tetrahydro-beta-carboline compounds having useful central nervous system activity. Further, there is provided tetrahydro-beta-carboline related compounds which are useful intermediates and have beneficial central nervous system activity. The invention provides formulations and methods for using the novel tetrahydro-beta-carboline and related compounds. Such compounds are particularly useful for the modulation of a 5-HT.sub.2B receptor.

Abstract: The present invention relates to a process of preparing quinacridone pigments in their specific crystal forms by oxidizing a premilled 6,13-dihydroquinacridone corresponding to the quinacridone pigment in a basic, aqueous reaction medium utilizing hydrogen peroxide as the oxidizing agent. The inventive process is an environmentally friendly process which yields a polymorphically homogeneous product in excellent yield.

Abstract: This application relates to a process for preparing quinacridones whereby the corresponding dihydroquinacridone is oxidized by subjecting a paste containing the dihydroquinacridone and an oxidizing agent to a high shear force mixing step.

Abstract: The present invention relates to a process of preparing quinacridone by oxidizing a 6,13-dihydroquinacridone salt corresponding to the quinacridone pigment with hydrogen peroxide as the oxidizing agent. The inventive process is economical and environmentally friendly and yields high performance quinacridone pigments in a high yield.

Abstract: A process for producing 2,5-di(arylamino)-3,6-dihydroterephthalic acid dialkyl ester having a high purity from 1,4-cyclohexanedione-2,5-di(carboxylic acid alkyl ester) at high yields for a short period of time; a process for producing quinacridone of which the byproduct content is small, from the above 2,5-di(arylamino)-3,6-dihydroterephthalic acid dialkyl ester; and a process for producing quinacridone of which the particle diameter is adjusted as desired, from the above 2,5-di(arylamino)-3,6-dihydroterephthalic acid dialkyl ester without adding a step of forming a pigment.

Abstract: Process for the preparation of pigment preparations, which comprises wet milling the crude pigments which are present in coarsely crystalline state, or prepigments or pigments which are present in a form in which they are difficult to disperse, in a concentration of from 20 to 60% by weight based on the total weight of the pigment preparation, in a flocculation-stable liquid medium and in a stirred ball mill which is operated with a peripheral stirrer speed of more than 12 m/s, under the action of nonmetallic grinding media with a diameter of less than or equal to 1.0 mm, until the desired degree of fine division is reached, and then isolating the pigment preparation.

Abstract: This invention relates to a process for the preparation of quinacridone pigments by(a) heating a reaction mixture comprising(i) a 2,5-dianilinoterephthalic acid, a 2,5-dianilino-3,6-dihydroterephthalic acid, or a 2,5-dianilino-3,6-dioxo-1,4-cyclohexadiene-1,4-dicarboxylic acid;(ii) about 0.1 to about 15 percent by weight, based on component (a)(i), of one or more sulfonyl-containing derivatives of 2,5-dianilinoterephthalic acid, 2,5-dianilino-3,6-dihydroterephthalic acid, and/or 2,5-dianilino-3,6-dioxo-1,4-cyclohexadiene-1,4-dicarboxylic acid; and(iii) about 3 to about 20 parts by weight, per part of component (a)(i), of a dehydrating agent,with the proviso that if either component (a)(i) or component (a)(ii) is a 2,5-dianilino-3,6-dihydroterephthalic acid or derivative thereof, reaction step (a) additionally comprises an oxidation step;(b) drowning the reaction mixture from step (a) with a liquid in which the quinacridone pigment is substantially insoluble; and(c) isolating the quinacridone pigment.

Abstract: Process for preparing linear unsubstituted .beta.-phase quinacridone pigments A process for preparing linear unsubstituted .beta.-phase quinacridone pigments or pigment preparations, which comprisesa) cyclizing 2,5-dianilinoterephthalic acid in polyphosphoric acid or polyphosphoric ester with a phosphorus pentoxide content of at least 84% by weight to form the quinacridone,b) subsequently hydrolyzing this quinacridone with water or with an aqueous mineral acid solution, preferably orthophosphoric acid solution, at a temperature of at least 40.degree. C., preferably from 60.degree. to 105.degree. C., to form the crude quinacridone pigment which is predominantly in the .alpha.-phase,c) then heating the crude .alpha.-phase quinacridone pigment to a temperature between 120.degree. and 200.degree. C. in the presence of a from 0.1 to 3% strength by weight, preferably from 0.

Abstract: A process for preparing quinacridone pigmentsA process for preparing pigments, mixed crystal pigments and pigment preparations based on linear unsubstituted or substituted quinacridones of the formula (I) ##STR1## in which the substituents R.sup.1 and R.sup.2 are identical or different and are hydrogen, chlorine, bromine or fluorine atoms or are C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or carboxamido groups which may be substituted by C.sub.1 -C.sub.6 -alkyl groups; or are phenoxy or C.sub.6 -C.sub.10 -aryl rings onto which further aromatic, aliphatic or heterocyclic rings can be fused, which process comprises hydrolyzing the reaction mixture resulting from cyclization of the respective dianilinoterephthalic acid with polyphosphoric acid or polyphosphate at a temperature of or above 110.degree. C.

Abstract: The present invention relates to a solid solution consisting of 60-90 mol-% of an asymmetric 2,5-dihydro-1,4-diketopyrrolo?3,4-c!pyrrole of the formula (I) ##STR1## in which G.sub.1 and G.sub.2 independently of one another are different substituted or unsubstituted aromatic radicals or pyridyl, but the volume of all substituents on G.sub.1 and G.sub.2 is greater than that of two methyl groups;and 40-10 mol-% of a 2,5-dihydro-1,4-diketopyrrolo?3,4-c!pyrrole of the formula (IIa) ##STR2## in which G.sub.3 and G.sub.4 independently of one another are different substituted or unsubstituted aromatic radicals or pyridyl, but the volume of all substituents on G.sub.3 and G.sub.4 is less than that of two butoxy groups;or 40-10 mol-% of a quinacridone of the formula (IIb) ##STR3## in which R.sub.9 is hydrogen, halogen, C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.4 alkoxy;which is a single-phase solid solution having the crystal structure of the asymmetric 2,5-dihydro-1,4-diketopyrrolo?3,4-c!pyrrole of the formula (I).

Abstract: Polarizing coatings are formed from dyestuffs which provide a stable liquid crystalline phase in a wide range of concentrations, temperatures and pH-values. Particles formed by aggregates of the liquid crystal molecules are oriented in a predetermined direction to polarize light. The stability of the liquid crystalline state allows orienting the particles by mechanical forces such as a shearing force applied when the liquid crystal (10) is spread on a support surface (20) by a knife-like doctor (90) or a tension deformation force acting on the meniscus of the liquid crystal deposited between two surfaces (20, 30) as the surfaces are peeled off one another. As a result, the polarizing coatings are formed in some embodiments by simple methods. In some embodiments, the polarizing coatings have a high lightfastness, a high thermal stability, and a high dichroic ratio.

Abstract: To produce defined isomer mixtures of compounds with spirocyclic beta-aminocarboxyl and/or beta-aminocarbonyl systems the invention supposes that they be dissolved in solvents which have good dissolving power for these compounds, whose relative permittivity is sufficient to stabilize the amphoteric intermediates occuring in isomerization, which as proton donors constitute hydrogen bridges, whose basicity is less than that of the compounds for isomerization and whose boiling point is so high that an adequate reaction speed can be attained by raising temperature. Further, the invention proposes that the isomerization be prevented, influenced, or terminated by altering at least one of these factors and or by altering the temperature.

Abstract: This invention relates to a process for the preparation of quinacridone pigments by(a) heating, at a temperature of about 80.degree. C. to about 145.degree. C., a reaction mixture containing(i) 2,5-dianilinoterephthalic acid, a 2,5-dianilino-3,6-dihydroterephthalic acid ester, and/or a derivative thereof,(ii) about 3 to about 15 parts by weight, per part of component (a)(i), of a dehydrating agent, and(iii) about 0.

Abstract: This invention relates to pigment compositions comprising an organic pigment treated with about 0.1 to about 20% by weight, based on the organic pigment, of an N-heteroarylamidomethyl pigment derivative having the formula (I) ##STR1## wherein, Q represents an organic pigment moiety,NHet represents a nitrogen-containing heteroaromatic group attached at a ring nitrogen atom to the carbonyl function of the amidomethyl linking group, andn is from 1 to 4.

Abstract: This invention relates to a process for the preparation of quinacridone pigments by(a) heating, at a temperature of about 80.degree. C. to about 145.degree. C., a reaction mixture containing(i) 2,5-dianilinoterephthalic acid, a 2,5-dianilino-3,6-dihydroterephthalic acid ester, and/or a derivative thereof,(ii) about 3 to about 15 parts by weight, per part of component (a)(i), of a dehydrating agent, and(iii) about 0.

Abstract: A process for producing 2,5-di(arylamino)-3,6-dihydroterephthalic acid dialkyl ester having a high purity from 1,4-cyclohexanedione-2,5-di(carboxylic acid alkyl ester) at high yields for a short period of time; a process for producing quinacridone of which the byproduct content is small, from the above 2,5-di(arylamino)-3,6-dihydroterephthalic acid dialkyl ester; and a process for producing quinacridone of which the particle diameter is adjusted as desired, from the above 2,5-di(arylamino)-3,6-dihydroterephthalic acid dialkyl ester without adding a step of forming a pigment.

Abstract: Disclosed are novel compounds having structural formula (I) ##STR1## or a pharmaceutically acceptable salt thereof, wherein X is hydrogen, halo, --CF.sub.3 or lower alkyl; Y is --(CH.sub.2).sub.n --, wherein n is 0, 1, 2 or 3, --C(O)--, --CH.sub.2 C(O)--, --CH.sub.2 CH.sub.2 C(O)-- or --CH(OH)--; A is --N(R)-- and B is --CH.sub.2 --, or A is --CH.sub.2 -- and B is --N(R)--; R is hydrogen, lower alkyl, lower alkanoyl, --CO.sub.2 R.sup.1, (a) or (b); R.sup.1 is hydrogen, lower alkyl or --CH.sub.2 CCl.sub.3 ; and - - - - represents an optional double bond, with the proviso that the ring containing Y has only one optional double bond. Also disclosed are pharmaceutical compositions comprising these compounds and their use in treating allergy and inflammation.

Abstract: Heat-stable, red pigment compositions comprising a physical mixture of 1,4-diketo-3,6-di(4-biphenylyl)-pyrrolo [3,4 c]-pyrrole and a 2,9-dichloroquinacridone pigments, processes for preparing the pigment compositions and the use of the compositions for pigmenting high-molecular-weight organic materials are disclosed.

Abstract: The present invention provides novel tetrahydro-beta-carboline compounds having useful central nervous system activity. Further, there is provided tetrahydro-beta-carboline related compounds which are useful intermediates and have beneficial central nervous system activity. The invention provides formulations and methods for using the novel tetrahydro-beta-carboline and related compounds. Such compounds are particularly useful for the modulation of a 5-HT.sub.2B receptor.

Abstract: The present invention relates to pigment and coating compositions that are used to prepare pigmented coatings that exhibit geometric metamerism or metallic flop. The pigment compositions comprise a small particle size pigment and a flop-enhancing agent, which flop-enhancing agent is a copper phthalocyanine, an indanthrone or a carbazole dioxazine compound. A method of enhancing the flop of a pigmented polymeric coating by incorporating one or more flop-enhancing agents into the composition is also disclosed.

Abstract: The present invention relates to a process for the preparation of 2,5-di-phenylamino-terephthalic acid and its dialkyl esters of the formula ##STR1## in which R is a hydrogen atom or a methyl or an ethyl group, by reaction of a succinic acid dialkyl ester with a sodium alcoholate in xylene, treatment of the resulting 2,5-dihydroxy-cyclohexadiene-1,4-di-carboxylic acid dialkyl ester with acid and aniline, dehydrogenation of the resulting 2,5-di-phenylamino-dihydro-(3,6)-terephthalic acid dialkyl ester by means of oxygen, if appropriate hydrolysis of the 2,5-di-phenylamino-terephthalic acid dialkyl ester formed and liberation of the 2,5-di-phenylamino-terephthalic acid from the di-sodium salt formed. The 2,5-di-phenylamino-dihydro-(3,6)-terephthalic acid dialkyl ester is reacted with pure oxygen in the presence of an alkali metal ion and/or an alkaline earth metal ion. This significantly decreases undesirable impurities.

Abstract: A process for producing highly pure 6,13-dihydroquinacridone, which is a suitable intermediate for effectively producing a quinacridone pigment, for a short period of time at high yields, the process comprising providing a cylindrical reactor, providing an atmosphere free of oxygen in the cylindrical reactor, heating the cylindrical reactor so that the temperature of at least a surface of an inner wall of a cylinder of the cylindrical reactor is in the range of from 250.degree. to 400.degree. C.

Abstract: Linear, unsubstituted quinacridone pigments of the .beta.-phase can be produced in an environmentally friendly manner bya) cyclizing 2,5-dianilinoterephthalic acid in polyphosphoric acid or a polyphosphoric ester to the quinacridone,b) then hydrolyzing the quinacridone with water at a temperature of at least 40.degree. C., preferably at from 60.degree. to 100.degree. C., to obtain a finely divided quinacridone pigment crude which is predominantly in the .alpha.-phase,c) then optionally wet grinding the finely divided quinacridone pigment crude from b) (pre-pigment), andd) then heating the crude pigment from b) or the pre-pigment from c) to a temperature between 120.degree. and 200.degree. C. in the presence of from 0.1 to 1.5 times the amount of an inorganic base, based on the weight of the crude pigment, in an inert liquid medium (solvent finish).To improve the depth and hue of the color, an oxidative treatment with a peroxodisulfate can be carried out subsequently.

Abstract: Compounds of formulaA(B).sub.x, (I),whereinx is an integer from 1 to 4,A is the radical of a chromophore of the quinacridone, anthraquinone, perylene, indigo, quinophthalone, isoindolinone, isoindoline, dioxazine, phthalocyanine or azo series, which radical contains x N-atoms attached to B, preferably with at least one directly adjacent or conjugated carbonyl group,B is a group of formula ##STR1## and, if x is 2, 3 or 4, may also be one, two or three hydrogen atoms. The symbols Q, R.sub.1, R.sub.2, R.sub.3, R.sub.4, X, Y, Z, m and n, are as defined in claim 1. These carbamate group-containing soluble chromophores am distinguished by outstanding solid state fluorescence in the UV range as well as the by ease with which they can be converted to the corresponding pigments in the substrate in which they are incorporated.

Abstract: A novel 4-acylaminopyridine derivative represented by the following formula (I) is disclosed. ##STR1## The 4-acylaminopyridine derivative of the present invention is useful as a medicine for treating disturbances of memory such as senile dementia and Alzheimer's disease, since it has an action of directly activating malfunctioned cholinergic neuron.

Abstract: An aqueous phase air oxidation process for the for the preparation of unsubstituted and substituted quinacfidone pigments is disclosed. The process involves an oxidation step wherein a 6,13-dihydroquinacridone is convened to the corresponding quinacfidone, utilizing a quinone compound and molecular oxygen as oxidizing agent, in a basic, aqueous reaction medium, in the presence of a nonionic, polar organic material which forms a second liquid phase in the basic reaction medium and which is present in a minor amount relative to the amount of aqueous base in the reaction medium. The quinacridones prepared by this process are useful as pigments.

Abstract: The present invention provides tetrahydro-betacarboline compounds having useful central nervous system activity.

Abstract: This invention relates to a process for the preparation of quinacridone pigments comprising(a) heating, at a temperature of about 80.degree. C. to about 145.degree. C., a reaction mixture comprising(i) 2,5-dianilinoterephthalic acid or a 2,5-dianilinoterephthalic acid derivative having one or more substituents in at least one aniline ring,(ii) about 2 to about 10 parts by weight, relative to component (a)(i), of a dehydrating agent, and(iii) about 0.01 to about 10 percent by weight, relative to component (a)(i), of a salt other than an iron salt;(b) drowning the reaction mixture from step (a) by adding said reaction mixture to about 3 to about 15 parts by weight, relative to component (a)(i), of a liquid in which the pigment is substantially insoluble;(c) isolating the quinacridone pigment; and(d) optionally, conditioning the quinacridone pigment.

Abstract: This invention relates to a process for the preparation of quinacridone pigments comprising(a) heating, at a temperature of about 80.degree. C. to about 145.degree. C., a reaction mixture comprising(i) 2,5-dianilinoterephthalic acid or a 2,5-dianilinoterephthalic acid derivative having one or more substituents in at least one aniline ring,(ii) about 2 to about 10 parts by weight, relative to component (i), of a strong acid, and(iii) at least about 0.4 mole percent, relative to component (i), of iron in the form of an iron salt;(b) drowning the reaction mixture from step (a) by adding said reaction mixture to about 3 to about 15 pads by weight, relative to component (i), of a liquid in which the pigment is substantially insoluble;(c) isolating the quinacridone pigment; and(d) optionally, conditioning the quinacridone pigment.

Abstract: The present invention provides pentacyclic pyrido[3,4-b]indoles having useful central nervous system activity.

Abstract: A general method for the direct preparation of pigmentary quinacridone solid solutions is disclosed. The disclosed process comprises oxidizing a mixture of dihydroquinacridones directly to a pigmentary quinacridone solid solution wherein the oxidation is carried out by heating a reaction mixture comprising the dihydroquinacridone mixture, an alkali metal hydroxide, a water miscible organic solvent, water and effective mounts of an oxidizing agent and a particle growth inhibitor. In addition, an analogous process useful for the direct pigmentary synthesis of .alpha.-quinacridone is disclosed. The pigments prepared by the disclosed processes do not require additional particle-size reducing after treatments in order to be useful as pigments.

Abstract: A process for the direct preparation of pigmentary 2,9-dichloroquinacridone, which comprises oxidizing 2,9-dichloro-6,13-dihydroquinacridone directly to pigmentary 2,9-dichloroquinacridone by heating a reaction mixture comprising 2,9-dichloro-6,13-dihydroquinacridone, an alkali metal hydroxide, a water-soluble organic solvent, water and effective amounts of an oxidizing agent and a phthalimidomethylquinacridone particle growth inhibitor. The process yields pigmentary 2,9-dichloroquinacridone directly; without the need for additional particle-size reducing aftertreatments.

Abstract: A novel 4-acylaminopyridine derivative represented by the following formula (I) is disclosed. ##STR1## The 4-acylaminopyridine derivative of the present invention is useful as a medicine for treating disturbances of memory such as senile dementia and Alzheimer's disease, since it has an action of directly activating malfunctioned cholinergic neuron.

Abstract: A process for the preparation of 2,9-dimethylquinacridone pigments or mixed crystal pigments or mixtures of 2,9-dimethylquinacridone and quinacridones which in the two outer fused benzene rings can be substituted, characterized by the form of their crystalline particles having an average ratio of length to width of <2:1 and an average particle size of <0.4 .mu.m, by adding to the solution of 2,9-dimethylquinacridone before or during the finishing of the corresponding crude quinacridones of the quinacridones mentioned in water or solvent mixtures at temperatures from about 60.degree. to about 200.degree. C., in each case a compound of the general formula (I) ##STR1## in an amount of about 1 to 20% by weight, in which Q is a quinacridone radical which is unsubstituted or substituted, Y is an --NR.sup.4 R.sup.5 group or the radical of a five-, six- or seven-membered heterocycle which contains one to three hetero atoms and can be substituted, R and R' are hydrogen or alkyl, and R.sup.1 to R.sup.