Abstract: Disclosed are a novel fluorene derivative, a liquid crystal composition comprising the same, and an optical film using the same liquid crystal composition. More particularly, there are provided a liquid crystal material for a viewing angle compensation film with high quality characteristics, which can improve a contrast ratio measured at an oblique angle to the front and minimize variations in color with viewing angles in a black state, a liquid crystal composition comprising the same liquid crystal material, and a compensation film obtained from the same liquid crystal composition.

Abstract: Disclosed is a novel liquid crystal compound, a liquid crystal composition comprising the same, and an optical film using the same liquid crystal composition. More particularly, there is provided a liquid crystal material of a viewing angle compensation film with high quality characteristics, which can improve a contrast ratio and minimize variations in color with viewing angles in a black state, a liquid crystal composition comprising the same liquid crystal material, and a compensation film obtained from the same liquid crystal composition.

Abstract: A process for producing an alcohol or a silyl ether thereof of formula (4): wherein R1 represents a hydrocarbon, a heterocyclic, or an alkoxycarbonyl group; R2 represents hydrogen or CO2R; X represents an aryl or an alkenyl group of formula (3): and R8 represents hydrogen or a silyl residue, by reacting a compound R1(C?O)R2 with a silane (R3)2R4Si—X, wherein R3 and R4 each represents an alkyl, an alkoxy, or an aryl group; in the presence of (i) a catalyst component containing copper fluoride or a catalyst component containing a copper compound and a fluoride and (ii) a bidentate phosphine compound or in the presence of a complex obtained from the foregoing components.

Abstract: A process for synthesizing arylamine compounds is provided. The process includes producing a dicarboxylic acid salt of an arylamine molecule by reacting a dicarboxylic acid arylamine with an alkyl salt to produce the dicarboxylic acid arylamine salt.

Abstract: The present invention relates to novel compounds suitable for or already radiolabeled with 18F, methods of making such compounds and use of such compounds for diagnostic imaging. Such labeled compounds are characerized by Formula II, wherein the moieties F, R1, R2, B1,2, Y1,2, Z1,2 and E have the meaning as defined in the specification and claims.

Abstract: Fluorine-containing silicon compounds having the general formula (1): wherein X1, X2, and X3 each are hydrogen, hydroxyl, halogen, a straight, branched or cyclic alkoxy group of 1 to 6 carbon atoms, or a monovalent organic group of 1 to 20 carbon atoms having a straight, branched, cyclic or polycyclic skeleton, Y is a divalent organic group, R1 and R2 are each independently hydrogen or a monovalent organic group of 1 to 20 carbon atoms having a straight, branched, cyclic or polycyclic skeleton, or R1 and R2 may bond together to form a ring with the carbon atom to which they are attached silicone resins obtained from the compounds of formula (1) has an appropriate acidity to enable formation of a finer pattern while minimizing the pattern collapse by swelling when used in a resist composition.

Abstract: The invention relates to novel silane compounds corresponding to the formula (I) below: A-E-X??(I) in which: X represents a silyl group capable of creating a covalent bond after reaction with the hydroxyl or hydride functional groups of a support; E represents an organic spacer group; A represents a group chosen from the groups of formulae below: in which: Z1 to Z5 independently represent a hydrogen atom or a halogen atom; Z6 and Z7 represent a group for protecting the phosphonic acid functional group, a hydrogen atom or a monovalent cation; Z8 to Z12 independently represent a group for protecting the carboxylic acid functional group, a hydrogen atom or a monovalent cation; and Z13 represents an imidazole, N-hydroxysuccinimide, nitrophenyl, pentafluorophenyl or acid anhydride group. Use of these silane compounds for functionalizing solid supports and for immobilizing biological molecules on these supports.

Abstract: The present inventors have obtained a PSQ derivative of a completely condensed type into which a functional group is readily introduced by using a novel PSQ derivative of an incompletely condensed type in which four alkaline metal atoms are bonded to silsesquioxane of a cage type having eight Si's. The above silsesquioxane derivative is represented by Formula (1). A silsesquioxane derivative to which alkaline metal atoms are bonded is represented by Formula (2). In Formula (1) and Formula (2), R is a group selected from alkyl, aryl and arylalkyl; Y is a group represented by Formula (a) or Formula (b); and M is a monovalent alkaline metal atom. X in Formula (a) and Formula (b) is hydrogen, halogen, a hydroxyl group or a monovalent organic group, and Z is —O—, —CH2— or a single bond. The preferred organic group is a functional group or a group having a functional group.

Abstract: Unique photoprotective compositions contain novel methyltrialkylsilanes bearing a cinnamate, cinnamamide, benzalmalonamide or benzalmalonate function, useful as sunscreens that are active in the field of UV radiation and also useful in methods for photostabilizing synthetic polymers or glasses.

Abstract: This invention describes protected 5,7-dihydroxy-4,4-dimethyl-3-oxoheptanoic acid ester and 5,7-dihydroxy-2-alkyl-4,4-dimethyl-3-oxoheptanoic acid ester for the synthesis of epothilones and epothilone derivatives and process for the production of these esters.

Abstract: The present invention relates to a novel organic silane compound, and more particularly, to a novel organic silane compound, useful in various applications, for the purpose of improving the affinity of an organic resin to an inorganic filler or improving the adhesion of a coating layer comprising matrix resin to a substrate. It is particularly useful for improving the adhesion of a polarizing plate adhesive for a liquid crystal display to a glass substrate, with little change over time even under hot and humid conditions.

Abstract: Polymerizable silicon-containing compounds of formula (1) wherein R1 is hydrogen, halogen or monovalent organic group are polymerized into polymers.

Abstract: The present inventors have obtained a PSQ derivative of a completely condensed type into which a functional group is readily introduced by using a novel PSQ derivative of an incompletely condensed type in which four alkaline metal atoms are bonded to silsesquioxane of a cage type having eight Si's. The above silsesquioxane derivative is represented by Formula (1). A silsesquioxane derivative to which alkaline metal atoms are bonded is represented by Formula (2). In Formula (1) and Formula (2), R is a group selected from alkyl, aryl and arylalkyl; Y is a group represented by Formula (a) or Formula (b); and M is a monovalent alkaline metal atom. X in Formula (a) and Formula (b) is hydrogen, halogen, a hydroxyl group or a monovalent organic group, and Z is —O—, —CH2— or a single bond. The preferred organic group is a functional group or a group having a functional group.

Abstract: Process for the preparation of organosilylated carboxylate monomers comprising the step of reacting an acyloxysilane with an unsaturated carboxylic acid, the monomers and their use as comonomer unit in the binder of antifouling coating compositions.

Abstract: The present invention provides image-forming compositions and photosensitive lithographic plates which are excellent in sensitivity to infrared radiation, latitude of development, treatable area in m2, and printing durability. Specifically, the present invention provides an image-forming composition comprising (A) a polymeric compound obtainable by the addition reaction of a resinous polymer having one or more phenolic hydroxyl groups with a silane coupling agent of the following general formula (1) or (2), (B) an acid generator, (C) an infrared absorber, and (D) an alkali-soluble resin, and a photosensitive lithographic plate having this image-forming composition applied onto a substrate.

Abstract: A mixture containing a monohydric alkyl alcohol and an alkoxysilane is purified by (i) adding an organic salt or an inorganic salt to the monohydric alkyl alcohol and the alkoxysilane; (ii) mixing the organic or inorganic salt with the monohydric alkyl alcohol and the alkoxysilane; and (iii) separating from (ii) a first phase containing the alkoxysilane, and a second phase containing the monohydric alcohol and the organic or inorganic salt. The preferred salt is lithium chloride, and the monohydric alkyl alcohol is most typically methyl alcohol or ethyl alcohol.

Abstract: A process for stabilizing organosilicon compounds bearing unsaturated groups during their preparation, distillation, and/or storage, the organosilicon compounds bearing unsaturated groups having been obtained by reacting a haloalkylsilane with a salt of an unsaturated organic acid, by adding one or more compounds of the formula I wherein R1 and R2 are identical or different linear or branched C1-20 alkyl, and the radicals R3 are identical or different and are hydrogen or linear or branched alkyl radicals having 1-20 carbon atoms.

Abstract: Chlorosilane compounds having a thexyl group which is a bulky substituent group are novel. The compounds are useful silylating agents because stable silylated products are obtained due to the bulky substituent group.

Abstract: Silanes of the general formula are prepared, wherein R1, R2 and R3 in the molecule are the same or different and represent aliphatic or aromatic hydrocarbon groups, R4 is a divalent hydrocarbon group with 4 to 12 carbon atoms and a lateral hydroxyl group, wherein the hydrocarbon group can be interrupted by an ether oxygen, R5 is a hydrophilic, ionic group. A method for synthesizing these compounds is described. The silanes greatly lower the surface tension of aqueous solutions, the surface tension being reduced to values of about 23 mN/m. The silanes are biologically degradable and have pronounced surfactant properties.

Abstract: Novel compounds comprising siloxane modified carboxylic acid substituted amines and salts thereof are provided. The compounds according to the invention provide many of the desirable properties of ethylenediamine tetraacetic acid and its salts in a stationary phase. A process for synthesis of the compounds according to the invention are also provided.

Abstract: Organosilicon compounds (P) containing &agr;,&bgr;-unsaturated carboxylic acid radicals, of the general formula (1) —A—O—C(O)—CR═CH2   (1), are prepared by a process in which, in a first step, organosilicon compounds (H) containing hydrogen atoms bonded directly to silicon are reacted with olefinically unsaturated compounds (U) containing a terminal double or triple bond, of the general formula (2) &OHgr;—O—C(O)—CRH—CH2—Z  (2), in the presence of metals or compounds from the platinum group as catalyst, to give organosilicon compounds (E) containing radicals of the general formula (3) —A—O—C(O)—CRH—CH2—Z  (3), and, in a second step, H—Z compounds are eliminated from organosilicon compounds (E), where A is a divalent organic radical, &OHgr; is a monovalent organic radical containing a terminal double or triple bond, R is an H atom or a methyl radical, and Z is Cl, I, Br or

Abstract: [Aim]This invention relates to a makeup containing a specific modified silicone obtained by an economical manufacturing method not requiring an esterification catalyst, having a high reaction rate and therefore leaving little unreacted material, and in particular relates to a makeup with good skin adhesion, good retention and excellent emulsion stability.

Abstract: Disclosed herein are a silane coupling agent and a method of preparing the same useful for a composite organic-inorganic material. The silane coupling agent is represented by the formula of R1R2R3Si—X, wherein R1, R2, and R3, respectively, represent straight or branched alkyl having 4 to 22 carbon atoms, alkoxy, phenyl, phenyl alkoxy, benzyloxy or phenyl alkyl group. The method comprises the steps of: dissolving a vinyl derivative in a solvent under a nitrogen or argon atmosphere; and reacting the resulting solution with an alkoxysilane derivative at a temperature of 20 to 200° C. for 1 to 72 hours in the presence of a metal catalyst. Alternatively, the method comprises the steps of: dissolving alkylmagnesium halide in a solvent under a nitrogen or argon; and reacting the resulting solution with haloalkoxysilane at a temperature of −78° C. to 50° C. for 0.1 to 5 hours.

Abstract: Silicone-containing organic compounds useful as modulators of mammalian nuclear hormone receptors, particularly the retinoid receptors and the farnesoid receptors.

Abstract: The invention relates to polysiloxanes containing carboxyl groups that are useful for imparting water-repellency to substrates, a process for their preparation, a water-repellent system containing such polysiloxanes, and a process for the production of hydrophobic substrates.

Abstract: This invention relates to composition of matter of certain euganol functionalized silicone polymers useful to make substantive antimicrobial agents. These compounds allow for the topical delivery of euganol to the skin surface, where it has a variety of desirable effects.

Abstract: Dendrimers were directly and covalently attached to solid supports via siloxy bonds. After complexation with transition metals, the dendrimers were used as catalysts. The supported dendrimers were stable and easily separated from the reaction mixture.

Abstract: The invention relates to varnished metal wires with one or more electrically insulating varnish coatings, at least one of the electrically insulating varnish coatings representing an organically modified silicic acid (hetero) polycondensate, which has been obtained by partial or total hydrolytic condensation of one or more hydrolytically condensable compounds of silicon and if necessary other elements from the group B, A1, P, Sn, Pb, the transition metals, the lanthanides and actinides, and/or from precondensates derived from the abovenamed compounds, if necessary in the presence of a catalyst and/or of a solvent by the action of water and moisture.

Abstract: A thermosetting resin composition obtained by heat treating, under the specified conditions, a mixture of a polyaddition thermosetting resin, a silicic compound (oligomer) having a functional group capable of causing an addition reaction with a curing agent for the polyaddition thermosetting resin, and water, followed by adding of a curing agent for the polyaddition thermosetting resin is useful for producing thermosetting resin molded articles, resin encapsulated semiconductor devices, automobile parts, etc., which are high in heat resistance, small in change of elastic modulus at high temperatures, and resistant to crack and peeling.

Abstract: A method for the preparation of a hydrophobic clay by contacting an aqueous suspension of the clay with an organosilane of formula R.sup.1.sub.a SiX.sub.4-a or an organosiloxane comprising units of formula R.sup.2.sub.n SiO.sub.(4-n)/2 in the presence of an acid and a water-miscible solvent. The resulting clay suspension is then contacted with a water-immiscible solvent to effect separation of the hydrophobed clay from the suspension.

Abstract: The invention includes hydrolyzable and polymerizable silanes, methods of making them and using them to obtain silicic acid(hetero)polycondensates and silicic acid(hetero)polymerizates. The hydrolyzable and polymerizable silanes have the formula I, ##STR1## wherein A=O, S, NH or C(O)O; wherein B=a straight chain or branched organic residue with at least one C.dbd.C double bond and from 4 to 50 carbon atoms;R is an alkyl group, alkenyl group, aryl group, alkylaryl group or an arylalkyl group;R' is a substituted or unsubstituted alkylene group, arylene group, arylenealkylene group or alkylenearylene group each having zero to ten carbon atoms, with the proviso that the substituted groups each have at least one oxygen atom, sulfur atom and/or amine group substituent;R.sup.

Abstract: The invention relates to an adhesive substance for improved adhesion between a vulcanizable polymer and a metallic reinforcing carrier.The use of an adhesive substance with the following structure is proposed in order to produce an improved adhesion between rubber and a metallic reinforcing carrier:X--(R).sub.n --(Ar).sub.i --(R).sub.m --Y,whereinX: --SH; --Si(Cl).sub.3 ; --Si(OR.sub.1).sub.3 ; --COOHwith R.sub.1 : alkyl remainder (branched and unbranched), particularly --CH.sub.3 ; --C.sub.2 H.sub.5 or --C.sub.3 H.sub.7 ;R: --CH.sub.2 --; --CF.sub.2 --; wherein 0.ltoreq.n,m.ltoreq.12, or--CH.sub.2 --CO--NH--CH.sub.2 --; --CF.sub.2 --CO--NH--CF.sub.2 --; --CH.sub.2 --CO--NH--CF.sub.2 --; --CF.sub.2 --CO--NH--CH.sub.2 --, wherein 0.ltoreq.n,m.ltoreq.4Ar: aromatic and/or heteroaromatic system, comprised of one or several of the following molecules:benzene, phenylene, aniline, thiophene, pyrrole, furane,with or without substituentswherein 0.ltoreq.i.ltoreq.

Abstract: A subject of the invention is the products of formula (I): ##STR1## in which: R.sub.1, R.sub.2 and R.sub.3, identical or different, represent a linear, branched or cyclic alkyl radical, an alkenyl or alkynyl radical, containing up to 8 carbon atoms, optionally substituted by one or more halogen atoms, an aryl radical optionally substituted by one or more halogen atoms, one or more hydroxyl radicals, one or more linear or branched alkyl radicals, optionally substituted by one or more halogen atoms, one or more O-alkyl or S-alkyl radicals optionally substituted by one or more halogen atoms,X represents a hydrogen atom, a halogen atom, an alkyl, alkenyl, alkynyl, O-alkyl, O-alkenyl, O-alkynyl, S-alkyl, S-alkenyl or S-alkynyl radical, optionally substituted by one or more halogen atoms and containing up to 11 carbon atoms, an aryl radical containing up to 14 carbon atoms, a C.tbd.N, NO.sub.2, NH.sub.2, ##STR2## CO.sub.2 alk.sub.3 radical, alk.sub.1, alk.sub.2 and alk.sub.

Abstract: The invention relates to hydrolyzable fluorinate silanes, methods of their roduction and of their use for producing silicic acid polycondensates and hetero silicic acid polycondensats The silanes in accordance with the invention are of the general formula: {[R'-(Y).sub.e ].sub.c+1 (C.sub.6 F.sub.4-c) (C.sub.6 F.sub.4).sub.d }.sub.f SiR.sub.a X.sub.b (I) in which the groups and indices are identical or different and have the following meaning:R=alkyl, alkenyl, aryl, alkylaryl or arylalkyl, substituted if required, each with 1 to 15 carbon atoms, whereby the groups may be interrupted by oxygen or sulfur atoms, ester, carbonyl, amide or amino groups;R'=I, Br, Cl (if d.noteq.0), F (if d.noteq.0), H (if X.noteq.H or R.noteq.methyl or e=1) or an organic group with 1 to 50 carbon atoms;X=hydrogen, halogen except fluorine, hydroxy, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl or NR".sub.

Abstract: The invention provides novel cross-linkable, photoactive silane derivatives and mixtures with 3-aryl-acrylic acid esters and amides. The present invention also provides orienting layers for liquid crystals, and non-structured and structured optical elements and multi-layer systems based on the silane mixtures and derivatives.

Abstract: The present invention relates to a highly enantioselective process for the preparation of enantiomerically pure cyclopentane- and -pentene .beta.-amino acids of the general formula (I) ##STR1## in which A and L, A and D or E and L, D and E, R.sup.2, R.sup.3, T and R.sup.1 have the meaning given in the description.

Abstract: The hydrolyzable and polymerizable silanes have the formula I, ##STR1## wherein X is hydrogen, a halogen, a hydroxy, an alkoxy group, an acyloxy oup, an alkylcarbonyl group, an alkoxycarbonyl group or --NR.sup.2.sub.2 group; wherein R.sup.

Abstract: Novel organosilane derivatized long-chain compounds containing halosilane and hydroxysilane groups are disclosed and claimed. A process for the syntheses of these novel compositions is also disclosed, which involves simple one-pot hydrosilylation reaction of substituted halosilanes with substituted long-chain olefinic compounds, and subsequent hydrolysis to form surface active silanol derivatives. Preferred embodiments include organosilane derivatives of fatty acids derived from tung oil, high erucic acid rape seed oil, and linseed oil. These compositions feature high surface activity in forming stable organic/water emulsions of various difficultly emulsifiable materials as compared with conventional emulsifying agents. These compositions are useful as reactive-dispersants, defoamers, reactive-surfactants in emulsion polymerization, crosslinkers, film formers, gloss enhancers, anticorrosive additives, adhesion promoters and as general property enhancers in coatings, adhesives and inks.

Abstract: An method for the synthesis of high-purity (meth)acryloxy-functional organosilicon compounds in which the generation of reaction by-products is inhibited and gelation of the reaction product does not occur comprising an addition reaction between(A) an acrylate ester or methacrylate ester of an aliphatically unsaturated alcohol and(B) a SiH-functional organosilicon compound in the presence of(C) a hydrosilylation-reaction catalyst and(D) a special type of compound such as the zinc salt of 2-mercaptobenzothiazole or zinc dimethyldithiocarbamate.

Abstract: Organosilicon compounds are described which contain a cyclic organic moiety between at least two reactive silane groups. The compounds are useful in coatings, adhesives, and sealants, and the like.

Abstract: The invention includes hydrolyzable and polymerizable silanes, methods of making them and using them to obtain silicic acid(hetero)polycondensates and silicic acid(hetero)polymerizates. The hydrolyzable and polymerizable silanes have the formula I, ##STR1## wherein A=O, S, NH or C(O)O;whereinB=a straight chain or branched organic residue with at least one C.dbd.C double bond and from 4 to 50 carbon atoms;R is an alkyl group, alkenyl group, aryl group, alkylaryl group or an arylalkyl group;R' is a substituted or unsubstituted alkylene group, arylene group, arylenealkylene group or alkylenearylene group each having zero to ten carbon atoms, with the proviso that the substituted groups each have at least one oxygen atom, sulfur atom and/or amine group substituent;R.sup.

Abstract: A process for the preparation of an organosilicon compound represented by formula (3): ##STR1## which process comprises reacting an organosilicon compound represented by formula (1) with a (meth)acrylic acid ester represented by formula (2) in the presence of a catalyst: ##STR2## The symbols in the above formulae are defined in the specification.

Abstract: Compounds of Formula I ##STR1## wherein the symbols are as defined in the specification.

Abstract: The invention relates to a process for preparing silanes or siloxanes having carboxyl functionalities, wherein a hydrogen silane or hydrogen siloxane compound is reacted with a tertiary butyl ester having an olefinic double bond and the sil(ox) ane-bonded tertiary butyl ester group is subsequently converted into the corresponding carboxyl group with elimination of isobutene.

Abstract: The invention is directed to water soluble silane compositions that are essentially alcohol free comprising compounds of the structure:(RO).sub.3-x (HO).sub.x Si(CH.sub.2).sub.3 (OCH.sub.2 CH.sub.2).sub.b OH(Ia ){(RO).sub.2-y (HO).sub.y Si(CH.sub.2).sub.3 (OCH.sub.2 CH.sub.2).sub.b O}.sub.z (IIa)wherein x ranges from 1 to 3, b ranges from 1 to 30, y is 0 or 1, and z ranges from 1 to 3, and R is an aryl or alkyl having from 1 to 10 carbon atoms. The invention further comprises methods for forming such compounds and for their use in preparing water soluble silane compositions by reaction with relative insoluble silane compounds terminated in functional groups selected from the group comprising epoxies, vinyls, mercaptos and acrylates.

Abstract: A hydrosilation process where a silicon hydride is reacted with an unsaturated reactant in the presence of a platinum catalyst and an aldehyde accelerator. The aldehyde accelerators are especially useful for facilitating the hydrosilation of unsaturated reactants where the unsaturation is in the internal portion of the reactant's structure, for example, as in cyclopentene and cyclohexene.

Abstract: The present invention provides novel silicon containing polyarylates of Formula I ##STR1## where R.sub.1 to R.sub.8 represent hydrogen, alkyl groups containing 1 to 5 methylene group or halogen atoms, R.sub.9 and R.sub.10 represents alkyl groups containing 1 to 5 carbon atoms or CF.sub.3 group and R.sub.11 and R.sub.12 represent alkyl groups with 1 to 5 carbon atoms or phenyl groups.

Abstract: A chiral catalyst is disclosed together with methods of using it for enantioselective syntheses. The chiral catalyst includes a nucleus with two metal atoms that has four bridging ligands oriented radially to the axis of the nucleus. Each of these ligands includes a two complexing atoms each complexed to one of the metal atoms. At least one of the bridging ligands includes a chiral center which is bonded to one of the complexing atoms. Preferably, all four of the bridging ligands include a chiral center bonded to one of the complexing atoms. The catalyst of the invention has been found to be useful in catalyzing carbenoid transformation reactions such as cyclopropanation.

Abstract: The present invention relates to compounds of the formula ##STR1## in which Z is a halogen atom, a cyano group or a hydroxyl group,n is 0, 1 or 2,R' is a radical of the formulaR"'--[Si(R*).sub.2 ].sub.x (CH.sub.2).sub.y R""-- (9),in whichx is the number 0 or 1,y is an integer from 1 to 18,R"'is a defined in the description,R* is identical or different, optionally substituted C.sub.1 - to C.sub.18 -hydrocarbon or hydrocarbonoxy radicals,R"" is a phenylene or biphenylene radical or a radical of the formula --E--, whereE is a divalent radical of the formula --O-- or --[Si(R*).sub.2 ].sub.z --, andz is the number 0 or 1,and the compounds contain at least one group of the formula --Si(R*).sub.2 -- per molecule, and the radicalR" is a cholesteryl radical, a radical as defined for R* or a radical of the formula --C.sub.6 H.sub.4 --R*,and the preparation and use thereof.

Abstract: Benzoic acid derivatives represented by the formula (I): ##STR1## wherein R.sub.1 represents hydrogen or lower-alkyl, R.sub.2 and R.sub.4 represent hydrogen, trimethylsilyl, or trimethylgermyl, R.sub.3 represents hydrogen, lower-alkyl, trimethylsilyl, or trimethylgermyl, R.sub.5 represents hydrogen, lower-alkyl, acetyl, or hydroxy, at least one of R.sub.2 and R.sub.3 being trimethylsilyl or trinethylgermyl, and R.sub.6 means hydroxy, lower-alkoxy, or a group of the formula --NR.sub.7 R.sub.8, wherein R.sub.7 and R.sub.8 mean hydrogen or lower-alkyl, and X represents a group of the formula --CONH--, --NHCO--, --COO--, --OCO--, --COCH.dbd.CH--, --COCH.dbd.C(OH), or --CH.dbd.CH--, which exhibit excellent effect as differentiation-inducing agents for neoplastic cells, especially leukemia cells, or a therapeutic agent for psoriasis or immune and inflammatory diseases, and a process for the preparation thereof, are disclosed.