Abstract: A toner for developing an electrostatic latent image including a binder resin, a colorant, and a modified polysiloxane having the general formula (1): ##STR1## In the above general formula, R 1 to R 4 , which may be identical or different, each stands for an alkyl group having 1 to 6 carbon atoms, a phenyl group, or a naphthyl group; R 5 and R 6 , which may be identical or different, each stands for a linear or branched, saturated hydrocarbon group having an average number of carbon atoms of from 16 to 600; and n and m each stands for a number of zero (0) or more

Abstract: A material containing, as a main component, an organic silicon compound represented by the following general formula: R.sup.1.sub.x Si(OR.sup.2).sub.4-x (where R 1 is a phenyl group or a vinyl group; R 2 is an alkyl group; and x is an integer of 1 to 3) is caused to undergo plasma polymerization or react with an oxidizing agent to form an interlayer insulating film composed of a silicon oxide film containing an organic component. As the organic silicon compound where R 1 is a phenyl group, there can be listed phenyltrimethoxysilane or diphenyldimethoxysilane. As the organic silicon compound where R 1 is a vinyl group, there can be listed vinyltrimethoxysilane or divinyldimethoxysilane.

Abstract: The neutral and cationic aminotroponiminate derivatives of germanium(II) have been investigated. The treatment of GeCl2·(1,4-dioxane) with [(i-Pr)2ATI]Li or [(Me)2ATI]Li in a 1:1 molar ratio gave the corresponding monochloro germanium(II) complex. Substitution of the chloride ion of [(i-Pr)2ATI]GeCl with weakly coordinating anions [CF3SO3]- and [(η5-C5H5)ZrCl2(μ-Cl)3ZrCl2(η5-C5H5)]- led to cationic germanium(II) species containing {[(i-Pr)2ATI]Ge}+ ion. Although NMR data of the cationic species show notable differences relative to their neutral analog, the solid state data show only minor changes in the C7N2Ge moiety. The Ge−N bond distances of the cations are not indicative of significant Ge−N π-bonding. These compounds feature some of the smallest N−Ge−N angles known for Ge(II) compounds. Attempted synthesis of the tetraphenylborate salt of {[(Me)2ATI]Ge}+ led to a phenyl group transfer product [(Me)2ATI]GePh·BPh3 with a Ge(II)−B bond. Details of the 1H, 13C NMR spectroscopy and X-ray crystal structures...

Abstract: Disclosed are compounds which inhibit .beta.-amyloid peptide release and/or its synthesis, and, accordingly, have utility in treating Alzheimer's disease. Also disclosed are pharmaceutical compositions comprising a compound which inhibits .beta.-amyloid peptide release and/or its synthesis as well as methods for treating Alzheimer's disease both prophylactically and therapeutically with such pharmaceutical compositions. Said compounds are represented by formula (I), wherein R1 is selected from the group consisting of: a) alkyl, alkenyl, alkaryl, alkcycloalkyl, aryl, cycloalkyl, cycloalkenyl, heteroaryl and heterocyclic; b) a substituted phenyl group of formula (II), wherein R is alkylene of from 1 to 8 carbon atoms, m is an integer equal to 0 or 1, and c) 1- or 2-naphthyl substituted at the 5, 6, 7 and/or 8 positions, R2 is selected from the group consisting of hydrogen, alkyl of from 1 to 4 carbon atoms, alkylalkoxy of from 1 to 4 carbon atoms, alkylthioalkoxy of from 1 to 4 carbon atoms; and R3 and R3' are independently selected from the group consisting of: (a) hydrogen, (b) alkyl, (c) -(R7)n(W)p, wherein R7 is an alkylene group, W is selected from the group consisting of (i) formula (A); (ii) heteroaryl; and (iii) N-heterocyclic, and n is an integer equal to 0 or 1, and p is an integer equal to 1 to 3; (d) -CH()CH2C(O)O-Q where Q is selected from the group consisting of alkyl, aryl, heteroaryl and heterocyclic; X' is hydrogen, hydroxy or fluoro; X'' is hydrogen, hydroxy or fluoro, or X' and X'' together form an oxo group, Z is selected from the group consisting of a bond covalently linking R1 to -CX'X''-, oxygen and sulfur.

Abstract: The electrocatalytic hydrogenolysis (ECH) of lignin model compounds has been investigated under galvanostatic control at Raney nickel electrodes in aqueous ethanol. The influence of current density, concentration of substrate and temperature on the efficiency of the carbon–oxygen bond hydrogenolysis was studied with benzyl phenyl ether and the optimum conditions leading to its total conversion were found. The effect, on the current efficiency, of replacing the phenyl group by an alkyl group (e.g. benzyl methyl ether) and of substituting hydrogens on aromatic rings by methoxy groups was investigated using the optimum electrolysis conditions. The electrocatalytic hydrogenolysis of β-phenoxyethylbenzene and α -phenoxyacetophenone, representatives of two other kinds of carbon–oxygen linkage in lignin, was also carried out.

Abstract: 1HNMR chemical shifts of solutions of the following cationic surfactants in D2O were determined as a function of their concentrations: cetyltrimethylammonium chloride, CTAC1, a 1:1 molar mixture of CTAC1 and toluene, cetylpyridinium chloride, CPyCl, cetyldimethylphenylammonium chloride, CDPhACl, cetyldimethylbenzylammonium chloride, CDBzACl, cetyldimethyl-2-phenylethylammonium chloride, CDPhEtACl, and cetyldimethyl-3-phenylpropylammonium chloride, CDPhPrACl. Plots of observed chemical shifts versus [surfactant] are sigmoidal, and were fitted to a model based on the mass-action law. Satisfactory fitting was obtained for the discrete protons of all surfactants From these fits, we calculated the equilibrium constant for micelle formation, K, the critical micelle concentration, CMC and the chemical shifts of the monomer, δmon and the micelle δmic 1H NMR-based CMC values are in excellent agreement with those which we determined by surface tension measurements of surfactant solutions in H2O, allowing for the difference in structure between D2O and H2O. Values of K increase as a function of increasing the size of the hydrophilic group, but the free energy of transfer per CH2 group of the phenylalkyl moiety from bulk water to the micellar interface is approximately constant, 1.9 ± 0.1 kJ mor−1. Values of (δmic−δmon) for the surfactant groups at the interface, e.g., CH3−(CH2)15− N + (CH3)2 and within the micellar core, e.g., CH3−(CH2)15−N+ were used to probe the (average) conformation of the phenyl group in the interfacial region. The picture that emerges is that the aromatic ring is perpendicular to the interface in CDPhACl and is more or less parallel to it in CDBzACl, CDPhEtACl, and CDPhPrACl.

Abstract: Insoluble s-triazine compounds (I) of the following formula are new: in which R1, R1' and R1" are: where -R2 and R2' are 1-3C alkyl groups; -R3 is H, an 1-4C alkyl group, or a 1-4C alkoxy group; -R4 is a 1-12C alkyl group; -X1 is H or a phenyl group, possibly substituted by a halogen, a 1-4C alkyl group or a 1-4C alkoxy group Also claimed is a composition (IV) to protect sensitive materials from UV radiation comprising (I) Also claimed is a method (V) of protecting sensitive materials from UV radiation comprising the application of (IV) to, or the incorporation of (IV) in, the sensitive material

Abstract: A photosensitive composition comprising (a) a resin selected from the group consisting of novolak resins and polyvinylphenol resins; (b) an amino compound derivative capable of curing the resin; (c) at least one member selected from the group consisting of cyanine compounds of the following formula (I) and polymethine compounds of the following formula (II), as a compound showing absorption in a near infrared wavelength region: wherein each of R 1 to R 8 which are independent of one another, is a hydrogen atom, a halogen atom or a nitro group, or the adjacent groups among R 1 to R 8 may be connected to each other to form a condensed benzene ring, each of R 9 and R 10 which are independent of each other, is an alkyl group which may have a substituent, a phenyl group which may have a substituent, an alkenyl group which may have a substituent, or an alkynyl group which may have a substituent, each of Y 1 and Y 2 which are independent of each other, is a sulfur atom or a dialkylmethylene group, L 1 is a penta- or hepta-methine group which may have a substituent, wherein two substituents on the penta- or hepta-methine group may be connected to each other to form a C 5-7 cycloalkene ring, and X - is a counter anion; wherein each of R 11 to R 14 which are independent from one another, is an alkyl group, each of R 15 and R 16 which are independent of each other, is an aryl group, which may have a substituent, L 2 is a mono-, tri- or penta-methine group which may have a substituent, and X - is a counter anion; and (d) a photosensitive acid-forming agent.

Abstract: The conjugate addition of lithium amides 2 to tert-butyl 4-(OR)-substituted-2-pentenoates 1 produced a mixture of the syn- and anti-amino esters (3 and 4) in high yields. Sterically bulky OR groups, such as trityloxy and tert-butyldiphenylsilyloxy, gave the syn diastereomer 3 either exclusively or predominantly. The syn-selectivity may be explained by a modified Felkin−Anh model. The use of tert-butyldimethylsilyloxy as an OR group afforded a nearly 1:1 mixture of diastereoisomers, and the use of the smallest MeO group produced a 63:37 mixture of the syn 3 and anti isomer 4. The presence of Me group at the α-position (C-2 position) of the enoate enhanced the syn diastereoselectivity up to 100%; the conjugate addition to tert-butyl 4-methoxy-2-methyl-2-pentenoate (17) gave the syn-isomer 18 exclusively. This enhancement may be explained by the combination of chelation and allylic strain model 19 in which the smallest H orients inside to avoid an allylic strain. A phenyl group at the γ-position enhanced the...

Abstract: The chloro bridges of the dinuclear complexes [(.65-cymene)-RuCl2]2 and [(.5-C5Me5)RhCl2]2 can be cleaved by reaction wht an N-phenyltriazolium perchlorate (1) and a base, resulting in the formation of (carbene)metal complexes. In this manner, abstraction of one ortho-proton of the phenyl group and elimination of HCl leads to pseudo-tetrahedral ruthenium (2) and rhodium (3) complexes, thereby creating a stereogenic center at the transition metal. By using enantiomerically pure triazolium perchlorates, the diastereoselective synthesis of these complexes with diastereomeric excesses of up to 95% can be achieved, with the possibility of separating the two diastereomers by column chromatography. The relative, and therefore also the absolute configuration of the ruthenium complex (RRu)-2b could be determined by X-ray structure analysis. A stereospecific substitution of chlorine by iodine or acetonitrile to form the diastereomerically pure complexes 4, 5 and 6 (the latter as cationic ruthenium complexes) allows a further variation of the ligands.

Abstract: Various N-[3,5-bis(trifluoromethyl)benzyl]-N-methylcarbamoyl heterocycles (1, 2 and 3) modified at rings A and B in the isoquinolone (1a) and pyrido[3,4-b]pyridine (2a) nuclei were prepared and evaluated for NK 1 receptor antagonistic activities. The structure-activity relationship studies on this series, along with conformational analysis, showed that (i) for ring A, 6-membered heterocycles are preferable to 5-membered heterocycles (a ca. 300-fold difference in potency), (ii) the 6-membered ring seems to function as an anchor by fixing the pendant phenyl group in a desirable orientation for receptor binding, and (iii) since compounds with aromatic rings (2) and those with aliphatic rings (3) as ring B both show good potency, this ring does not seem to be essential for receptor recognition. Among the compounds synthesized, the tetrahydropyridine derivatives 3a, 3b and 3f exhibited excellent inhibitory effects both in vitro and in vivo, with potent activity upon oral administration (ED 50 = 0.20-0.27mg/kg) (capsaicin-induced plasma extravasation in guinea pig trachea).

Abstract: Tri-substituted phenyl derivatives having the general formula (I): ##STR1## In a preferred embodiment, Y is preferably an --XR a group, X is preferably --O--, Z is preferably an --XR 5 group, R a is preferably hydrogen or an optionally substituted alkyl group, R 1 is preferably an --NHC(--NCN)NHR 13 or --NHC(═CHNO 2 )NHR 13 group, R 2 , R 3 and R 4 are preferably hydrogen, R 5 is preferably an optionally substituted alkyl, alkenyl, cycloalkyl, cycloalkenyl or heterocycloalkyl group, R 12 is preferably hydrogen or a C 1-3 alkyl group, R 13 is preferably hydrogen, a C 1-3 alkyl group, an optionally substituted phenyl group or an optionally substituted phenylC 1-3 alkyl group, Ar 1 is preferably an optionally substituted nitrogen containing heteroaryl group, and Ar is preferably a phenyl group. Compounds of the invention are potent and selective phosphodiesterase type IV inhibitors and are useful in the prophylaxis and treatment of various diseases, such as asthma, which are associated with an unwanted inflammatory response or muscular spasm.

Abstract: An examination of the α-arylation of a number of ketones and their enolate salts by p-methoxyphenyllead triacetate provides further evidence for a very marked selectivity in the arylation reaction. It is found that the reaction proceeds well at tertiary α-carbons and at secondary centres activated by the presence of a phenyl group, but fails where the secondary centre is unactivated and at primary α-carbons.

Abstract: Compounds of formula (I), wherein R1 is H, C1-6 alkyl optionally substituted by one or more halogen atoms, halogen, CN, C1-6 alkoxycarbonyl optionally substituted by one or more halogen atoms, NO2, CHO, CONH2, CSNH2 or C1-6 alkanoyl optionally substituted by one or more halogen atoms; Ar is a ring "A" where "A" is a phenyl group, or "A" is a 5- or 6-membered heteroaryl group, or Ar is a fused bicyclic moiety "AB" where the "A" ring is as defined above and the "B" ring fused thereto in "AB" is a 5- or 6-membered saturated or partially or fully unsaturated carbocycle, or saturated or partially or fully unsaturated heterocycle R2 is H, halogen, C1-6 alkyl optionally substituted by one or more halogen atoms, C2-6 alkenyloptionally substituted by one or more halogen atoms, C2-6 alkynyl optionally substituted by one or more halogen atoms, NH2,NH(C1-6 alkanoyl optionally substituted by one or more halogen atoms), NH(C1-6 alkoxycarbonyl optionally substituted by one or more halogen atoms), N(C1-6 alkoxycarbonyl optionally substituted by one or more halogen atoms)2, NH(C1-6 alkyl optionally substituted by one or more halogen atoms), N(C1-6 alkyl optionally substituted by one or more halogen atoms)2, NHCONH(C1-6 alkyl optionally substituted by one or more halogen atoms), N-pyrrolyl, NHCONH(phenyl optionally substituted by one or more halogen atoms),N=CH(phenyl optionally substituted by one or more halogen atoms), OH, C1-6 alkoxy optionally substituted by one or more halogen atoms, SH or S(O)m(C1-6 alkyl optionally substituted by one or more halogen atoms); R3, R4, R5, R6 and R7 are each independently H, halogen, nitro, C1-6 alkoxycarbonyl optionally substituted by one or more halogen atoms, C1-6 alkyl optionally substituted by one or more halogen atoms, CN, C1-6 alkanoyl optionally substituted by one or more halogen atoms, CONH2, CSNH2, C1-6 alkoxy optionally substituted by one or more halogen atoms, S(O)m(C1-6 alkyl optionally substituted by one or more halogen atoms) or SF5; Such compounds and salts have useful parasiticidal qualities.

Abstract: The new cyclic phosphine O2S[(t-Bu)MeC6H2O]2PPh (1) was used to prepare the new cyclic tetraoxyphosphoranes O2S[(t-Bu)MeC6H2O]2PPh(O2C6Cl4) (2) and O2S[(t-Bu)MeC6H2O]2PPh(O2C6H4) (3) by oxidative addition reactions. In similar reactions, the new cyclic pentaoxyphosphoranes O2S[(t-Bu)MeC6H2O]2P(OCH2CCl3)3 (4), O2S[Me2C6H2O]2P(OPh)3 (5), and O2S[(t-Bu)MeC6H2O]2P(OC6F5)3 (6) were formed from acyclic phosphites and the appropriate diol. Yields ranged from 51% to 66%. X-ray studies revealed hexacoordinated representations for 2 and 6 while 3−5 are pentacoordinate in trigonal bipyramidal geometries. For 3 and 4, the eight-membered rings are positioned diequatorially in anti chair conformations, whereas for 5, this ring occupies axial−equatorial sites in a syn twist-boat form. Tetraoxyphosphorane 3 is unique in locating the least electronegative ligand, the phenyl group, in an axial position. Oxygen donor action from the sulfone SO2 group led to a displacement from a square pyramid to an octahedron to the extent...

Abstract: Disclosed are ruthenium and osmium carbene compounds which are stable in the presence of a variety of functional groups and which can be used to catalyze olefin metathesis reactions on strained and unstrained cyclic and acyclic olefins. Specifically, the present invention relates to carbene compounds of the formula ##STR1## wherein: M is Os or Ru; R and R 1 are independently selected from hydrogen and substituent groups C 2 -C 20 alkenyl, C 2 -C 20 alkynyl, C 1 -C 20 alkyl, aryl, C 1 -C 20 carboxylate, C 2 -C 20 alkoxy, C 2 -C 20 alkenyloxy, C 2 -C 20 alkynyloxy, aryloxy, C 2 -C 20 alkoxycarbonyl, C 1 -C 20 alkylthio, C 1 -C 20 alkylsulfonyl or C 1 -C 20 alkylsulfinyl; each substituent group optionally substituted with C 1 -C 5 alkyl, a halogen, C 1 -C 5 alkoxy or with a phenyl group optionally substituted with a halogen, C 1 -C 5 alkyl or C 1 -C 5 alkoxy; X and X 1 are independently selected from any anionic ligand; and L and L 1 are each trialkyl phosphine ligands where at least one of the alkyl groups on the phosphine is a secondary alkyl or a cycloalkyl. A broad array of metathesis reactions are enabled including ring-opening metathesis polymerization of cyclic olefins, ring closing metathesis of acyclic dienes, cross metathesis involving at least one acyclic or unstrained cyclic olefin, depolymerization of unsaturated polymers and synthesis of telechelic polymers.

Abstract: The present invention relates to novel benzimidazole compounds, represented by general formula (I) in which o is 0, 1, 2, or 3; R1 represents an alkyl group, a phenyl group, or a monocyclic heterocyclic group, which groups may be substituted one or more times with substituents selected from alkyl, cycloalkyl, cycloalkyl-alkyl, alkoxy, halogen, trifluoromethyl, cyano, amino, and nitro; or R1 represents a cyano group or a group of the formula -alkyl-CO?2R?2, alkenyl-CO?2?R?2, -CO-R2, -CO?2(CH2)mR2, or -C(R?3)=N-OR2, R11? represents a group of formula -CO?2?-R?9, or R11? represents a group of general formula (II) in which n is 0, 1, 2 or 3; or R11 may represent a group of general formula (III), in which n is 0, 1, 2, or 3; the novel compounds of the invention are useful in the treatment of central nervous system diseases and disorders, which are responsive to modulation of the GABA?A? receptor complex, such as for example anxiety, sleep disorders, anaestesia, memory disorders, and epilepsia or other convulsive disorders.

Abstract: Novel compounds which are effective PDE IV inhibitors are disclosed. The present invention is directed to compounds having the general formula I ##STR1## wherein: X is a halogen; Q is --CH 2 --CH 2 --, --CH 2 --, a single or a double bond, or --NR 1 --; R 1 is a C 3-7 monocyclic ring structure containing at least one carbon atom and comprising one or more chalcogen atoms selected from the group consisting of nitrogen, sulfur and oxygen, wherein the monocyclic ring is unsaturated, partially unsaturated or saturated, and is optionally substituted with alkyl, cycloalkyl, alkoxy, cycloalkoxy, hydroxy or halogen; or is a bicyclic structure, comprised of a phenyl ring fused to a monocyclic ring structure as defined above, or comprised of two fused monocyclic ring structures, each ring containing at least one carbon atom and comprising one or more chalcogen atoms selected from the group consisting of nitrogen, sulfur and oxygen, wherein the monocyclic ring is unsaturated, partially unsaturated or saturated, and is optionally substituted with alkyl, cycloalkyl, alkoxy, cycloalkoxy, hydroxy or halogen. R 2 is a phenyl group or a C 3-7 monocyclic ring structure containing at least one carbon atom and comprising one or more chalcogen atoms selected from the group consisting of nitrogen, sulfur and oxygen, wherein the monocyclic ring may be unsaturated, partially unsaturated or saturated, and is optionally substituted with alkyl, cycloalkyl, alkoxy, cycloalkoxy, hydroxy or halogen.

Abstract: cis-4‘,7-Dihydroxyisoflavan-4-ol (4) and trans-4‘,7-dihydroxyisoflavan-4-ol (5), two proposed metabolites of daidzein (4‘,7-dihydroxyisoflavone), have been synthesized and fully characterized for the first time. The vicinal coupling constants of the pyran ring protons are compatible with a half-chair conformation. The cis isomer is anancomeric while the trans isomer consists of a 68:32 mixture of two ring inversion conformers. Molecular mechanical calculations are in agreement with the half-chair conformation of the pyran ring and suggest that the cis isomer is biased because of an unfavorable gauche interaction of the equatorial hydroxyl and the axial phenyl group. The isoflavanols 4 and 5 are comparable to genistein (4‘,5,7-trihydroxyisoflavone) in antitumor activity against human prostate cancer cells.

Abstract: Six styryl pyrazine compounds, some of which have steric hindrance to rotate and some have twist freedom, were synthesized in this work. The effects of solvent polarity and viscosity on the photophysical and luminescent behavior of these compounds were preliminarily studied. Results indicated that the blocking of the double-bond twist by a sufficiently rigid bridge increases fluorescence quantum yields dramatically and the rotation of a single bond connecting the double bond and the phenyl group is favorable to form a single-bond twisted state (T*), which is the state responsible for the main channel of fluorescence emission. The reason for the higher fluorescence quantum yield of distyryl pyrazine was thought to be involved with the lower probability of transition from the Frank-Condon state (S 1) to the phantom state (P*). Studies were also extended to develop a novel probe to detect the special microviscosity.

Abstract: A gelatinous external skin treatment composition comprising (1) spherical powder of organopolysiloxane elastomer having an average particle size of 1.0 to 15.0 µm, (2) silicone oil and (3) polyether modified silicone having the formula (I): wherein A represents a methyl group, phenyl group, or B explained below, B is a polyoxyalkylene group having the formula: ―C3H6O(C2H4O)a(C3H6O)bR', wherein R' is a group selected from the group consisting of a hydrogen atom, acyl group, and C1 to C4 alkyl groups, a is an integer of 5 to 50, and b is an integer of 5 to 50, R is a methyl group or phenyl group, m is an integer of 50 to 1000, and n is an integer of 0 to 40, provided that at least one polyoxyalkylene group is present in the molecule, and optionally (4) a lower alcohol having 3 carbon atoms or less and/or water.

Abstract: Phosphites which are useful as a deterioration inhibitor for organic material and are represented by the following formula: ##STR1## wherein R 1 , R 2 , R 5 and R 6 represent a hydrogen atom, an alkyl group, a cycloalkyl group, an alkylcycloalkyl group, an aralkyl group or a phenyl group; R 3 represents hydrogen atom or an alkyl group; R 4 represents a hydrogen atom, an alkyl group, a cycloalkyl group, an alkylcycloalkyl group, an aralkyl group or a phenyl group, or the two R 4 together form a direct bond, a group represented by --S-- or an optionally substituted methylene group; A represents an alkylene group; W represents a group represented by --O-- or a group represented by --NR 7 wherein R 7 represents a hydrogen atom, an alkyl group, etc.; B represents an alkylene group; and one of Y and Z represents a hydroxyl group, an alkoxy group or an aralkyloxy group, and the other one represents hydrogen atom or an alkyl group.

Abstract: Studies on the photoinduced electron transfer (PET) reactions of isobutylene (2-methylpropene, 1) in the absence of methanol have identified a new photochemical nucleophile−olefin combination, aromatic substitution (photo-NOCAS) reaction. Under these conditions acetonitrile was found to act as the nucleophile and to combine with the alkene radical cation. The resulting distonic radical cation then adds to the radical anion of 1,4-dicyanobenzene (2-•). The final product (6) results from cyclization into the ortho postion of the phenyl group. This product formation is rationalized on the basis of the relatively high oxidation potential of the alkene (i.e., one-electron oxidation yields a reactive radical cation), the fact that addition of the nucleophile (acetonitrile) to the radical cation is relatively unhindered, and the relatively low acidity of the radical cation due to the low radical stability of the allylic radical formed upon deprotonation. High-level ab initio molecular orbital calculations were u...

Abstract: The invention relates to a compound, and pharmaceutically acceptable salts, having formula (I), wherein: R represents an alkyl or alkynyl group having 1-4 carbon atoms, or a phenyl group optionally substituted by C1-4 alkyl, alkylthio, alkoxy, halogen, nitro, acylamino, methylsulfonyl or methylenedioxy, or represents tetrahydronaphthyl; R1 represents hydrogen, trifluoro (C?1-4?) alkyl, alkyl or alkynyl; X represents hydrogen, alkyl having 1-4 carbon atoms, alkoxy, trifluoroalkyl, hydroxy, halogen, methylthio or aralkoxy; R?2? represents: a C?1?-C10 alkyl group; a phenyl group optionally substituted by one or more of the following groups: a C1-C10 alkyl group, a halogen group, a nitro group, hydroxy group, and/or an alkoxy group.