Abstract: In a compound of the formula I (reactive polymer), L is a, polymer, XY is a reactive radical which is inert toward NCO groups and splits off one or more protective groups Y under acidic, neutral or basic conditions and the radical X bears, after Y has been split off, at least two groups which are reactive toward isocyanates. Also provided are processes for preparing such a polymer and for preparing V a polymer polyol which is obtainable by reacting a polymer of the formula I with an acid or base. A polymer polyol as is obtainable by treatment of a reactive polymer according to the present invention in the neutral, acidic or basic range can be used to produce a polyaddition product or polycondensation product.

Abstract: The present invention provides a citral acetal capable of sustaining a lemon aroma unique to citral and a perfume composition comprising the citral acetal, as well as an LDH inhibitor and a deodorant, cosmetics and a skin agent for external application, comprising the LDH inhibitor.

Abstract: This invention provides an improved process for cis-1-{2-[4-(6-methoxy-2-phenyl-1,2,3,4-tetrahydronaphthalen-1-yl)phenoxy]ethyl}pyrrolidine which is an intermediate for the preparation of (−)cis-6-phenyl-5-[4-(2-pyrrolidin-1-yl-ethoxy)-phenyl]-5,6,7,8-tetrahydronaphthalene-2-ol which is useful for the treatment of osteoporosis.

Abstract: Novel 4-methylene-1,3-dioxolanes of the general formula I in which R1 denotes hydrogen or alkyl, X denotes a single bond, C1-C18 alkylene, cycloalkylene, arylalkylene, —CH2(OCH2CH2)n— or —CH2(OCH(CH3)CH2)n—, in which n is an integer from 1 to 100, and Z means a functional group selected from among —OH, —COOR′ or —OCOR′, in which R′ denotes hydrogen or C1-C8 alkyl, are described, as are a process for the production thereof and the intermediates used in this process.

Abstract: Process for the preparation of malondialdehyde-derivatives by reacting vinylesters with orthoesters in the presence of a precious metal catalyst.

Abstract: This invention provides an improved process for cis-1-{2-[4-(6-methoxy-2-phenyl-1,2,3,4-tetrahydronaphthalen-1-yl)phenoxy]ethyl}pyrrolidine which is an intermediate for the preparation of (-)cis-6-phenyl-5-[4-(2-pyrrolidin-1-yl-ethoxy)-phenyl]-5,6,7,8-tetrahydronaphthalene-2-ol which is useful for the treatment of osteoporosis.

Abstract: A process for preparing easily and economically a 1,3-dioxolane-4-methanol compound in a racemic form or an optically active form with high purity and in high yield.The process comprises reacting an alkali metal or alkaline earth metal salt of an alcohol or a carboxylic acid with a halogenomethyl-1,3-dioxolane which is prepared by acetalizing a halogeno-1,2-propanediol of a formula (1) wherein X is a halogen atom, in an acid catalyst to conduct esterification or etherification, and then hydrolyzing the ester group and hydrogenolyzing the ether group to prepare a 1,3-dioxolane-4-methanol compound of a formula (5) wherein R.sup.1 and R.sup.2 are hydrogen atom, alkyl having 1 to 4 carbon atoms or phenyl, and R.sup.1 and R.sup.2 may form a cycloalkyl ring having 3 to 6 carbon atoms with the adjacent carbon atoms.

Abstract: The present invention provides substituted 3,3-diphenyl indanone, indane and indole compounds, as well as analogues thereof, which are specific, potent and safe inhibitors of mammalian cell proliferation. The compounds can be used to inhibit mammalian cell proliferation in situ as a therapeutic approach towards the treatment or prevention of diseases characterized by abnormal cell proliferation, such as cancer.

Abstract: A process for preparing a 1,3-dioxolane-3-methanol (5) in a racemic form or an optically active form involves reacting with an alcohol in a base (i) a 3-halogeno-1,2-propanediol (1a) in which X is halogen atom, or (ii) a glycidol effecting a 3-alkoxy-1,2-propanediol, acetalizing the 3-alkoxy-1,2-propanediol in an acid, and hydrogenolyzing the resulting 4-alkoxy-1,3-dioxolane in a reduction catalyst to effect the 1,3-dioxolane-3-methanol (5) in which each of R.sup.1 and R.sup.2 is a hydrogen atom, alkyl having 1 to 4 carbon atoms or phenyl, or R.sup.1 and R.sup.2 together form a cycloalkyl ring having 3 to 6 carbon atoms.

Abstract: The present invention relates to a compound represented by the following general formula (1) ##STR1## (wherein X represents O, S, SO, SO.sub.2, or NH, Y is a substituted or unsubstituted hydrocarbon residue containing 1 through 6 carbon atoms and having an overall molecular weight of not less than 15 and not more than 400, and the hydrocarbon residue, when the residue is ring, may contain one or two hetero-atoms in the ring, and Z is a carboxyl group, a group derived therefrom or an aliphatic hydrocarbon residue having from 1 to 4 carbon atoms which may be substituted or unsabstituted) or a pharmacologically acceptable salt thereof (excluding (1R,2S)-2-[(2R)-(2-acetyl-amino-2-carboxyethyl)thiomethyl]-3-oxo-1-cyclope ntane-carboxylic acid (cystacyclin)), a method for production thereof and a medicinal use thereof. The compound of the present invention is useful as a neuron differentiation accelerator.

Abstract: A process for preparing .alpha.-hydroxy acids by heating ammonium salts of .alpha.-hydroxy acids of general formula (I), removing the formed ammonia and water, adding water to the residue, and heating the obtained mixture, wherein R is hydrogen, C.sub.1 -C.sub.6 alkyl, alkyl(C.sub.1 -C.sub.6)thioalkyl (C.sub.1 -C.sub.6), phenyl or the like. This process is freed from the problem of disposal of by-products such as ammonium bisulfate and makes it possible to prepare a free .alpha.-hydroxy acid from an ammonium salt thereof economically and in a high yield.

Abstract: The present invention provides substituted 3,3-diphenyl indanone, indane and indole compounds, as well as analogues thereof, which are specific, potent and safe inhibitors of mammalian cell proliferation. The compounds can be used to inhibit mammalian cell proliferation in situ as a therapeutic approach towards the treatment or prevention of diseases characterized by abnormal cell proliferation, such as cancer.

Abstract: An improved process to make gemcitabine hydrocrhloride, the improvement consisting essentially of making the lactone intermediate, 2-deoxy-2,2-difluoro-D-erythro-pentafuranose-1 ulose-3,5-dibenzoate: ##STR1## from D-erythro-2-Deoxy-2,2-difluoro 4,5-O-(1-ethylpropyl)-idene) pentoic acid tert Butyl ester wherein, the D-erythro-2-deoxy-2,2 difluoro-4,5-O-(1-ethylproyl)-ideno) pentoic acid tert-Butyl ester is prepared by the process of reacting S-tert-butyl difluoroethane thioate with 2,3-O (1-ethylpropylidene)-D-glyceraldehyde, in a solvent and in the presence of a strong base; with the proviso that the process is conducted in the absence of a catalyst and in the absence of a silyl containing compound.

Abstract: A liquid crystalline compound of formula ##STR1## wherein B and D are each independently of the other C.sub.6 -C.sub.24 alkyl, ##STR2## L is ##STR3## methyl or C.sub.10 -C.sub.18 alkyl, wherein R.sub.1 is C.sub.4 -C.sub.18 alkyl, with the proviso that when L is methyl, at least one of B and D is C.sub.6 -C.sub.24 alkyl;R2 is hydrogen, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, halogen, cyano or nitro,R3, R4 and R5 are each independently of one another hydrogen, OR6, SR6, SeR6, --NHR6, --NR6R7, ##STR4## with the proviso that at least one of R3, R4 and R5 is not hydrogen, R6 is C.sub.7 -C.sub.37 alkyl, C.sub.7 -C.sub.37 alkylene or C.sub.5 -C.sub.18 alkyl which is interrupted by 1 to 6 hetero atoms selected from the group consisting of O, S and N,R7 is hydrogen or R9,R8 is hydrogen or C.sub.1 -C.sub.4 alkyl, andR9 is C.sub.1 -C.sub.12 alkyl, C.sub.2 -C.sub.12 alkylene or C.sub.3 -C.sub.12 alkyl which is interrupted by 1 to 6 hetero atoms selected from the group consisting of O, S and N.

Abstract: An epoxylated DBR, dibenzoylresorcinol and various derivatives thereof have been prepared to show usefulness in coatings due to compatibility and solubility. Such coatings can be acrylics, epoxies, or silicone hardcoats which are thermally or photo cured thermoset, or thermoplastic coating materials in a variety of solvent types. The disclosed UV absorber also has the advantage of a higher molecular weight and lower volatility than DBR alone thus providing processing advantages.

Abstract: Cyclic acetals or ketals are prepared by reacting a polyol with the appropriate aldehydes or ketones, with part of the aldehyde or ketone being distilled out during the reaction.

Abstract: .alpha.,.alpha.-Difluoro-.beta.-hydroxy thiol esters of Formula (III): ##STR1## wherein: R.sup.c and R.sup.d are independently selected from the group consisting of H, C.sub.1 -C.sub.6 alkyl, substituted C.sub.1 -C.sub.6 alkyl, S-tert-butyl difluorothioacet-2-yl, C.sub.3 -C.sub.8 cycloalkyl, C.sub.3 -C.sub.8 cycloalkenyl, substituted C.sub.3 -C.sub.8 cycloalkyl, substituted C.sub.3 -C.sub.8 cycloalkenyl, aryl, substituted aryl, C.sub.6 -C.sub.10 fused aromatic rings, and substituted C.sub.6 -C.sub.10 fused aromatic rings; orR.sup.c and R.sup.d together make up a ring selected from the group consisting of C.sub.3 -C.sub.8 cycloalkyl, C.sub.3 -C.sub.8 cycloalkenyl, substituted C.sub.3 -C.sub.8 cycloalkyl and substituted C.sub.3 -C.sub.8 cycloalkenyl;R.sup.e is selected from the group consisting of C.sub.1 -C.sub.10 alkyl, substituted C.sub.1 -C.sub.10 alkyl, aryl, substituted aryl, C.sub.3 -C.sub.8 cycloalkyl, C.sub.3 -C.sub.8 cycloalkenyl, substituted C.sub.3 -C.sub.8 cycloalkyl and substituted C.sub.3 -C.sub.

Abstract: Polyol ether derivatives, a method for producing the polyol ether derivatives, and a working fluid composition for a refrigerating machine containing a hydrofluorocarbon and a refrigeration oil containing the polyol ether derivatives as a base oil.

Abstract: The present invention provides a purified retinoid compound characterized by a molecular mass of about 320 daltons and an atomic composition of C.sub.20 H.sub.32 O.sub.3. The present invention also provides a purified retinoid compound having the structure: ##STR1## wherein the configuration of the C7, C9, and C11 double bond independently is Z or E and the absolute configuration at C13 and C14 is independently R or S; wherein R1 is alkyl, alkyl halide, alcohol, ester, ether, aldehyde, ketone, carboxylic acid, carboxylic ester, acyl halide, amide, nitrile, or amine; R2 and R3 are independently hydroxyl, halide, alkoxy, ester, alkyl, alcohol, ether, aldehyde, ketone, carboxylic acid, carboxylic ester, nitrile, amine, azide, alkyl halide, acid halide, acid azide, or amide; or wherein R2 and R3, or R1 and R2 are replaced by a 13,14-oxirane or a 14,15-oxirane group, respectively.

Abstract: The present invention relates to novel substituted bicyclic 2-mesityl-cyclopentane-1,3-dione derivatives of the formula (I) ##STR1## in which A and Q together represent alkanediyl or alkenediyl, which is in each case optionally substituted by halogen, hydroxyl, mercapto or in each case optionally substituted alkyl, alkoxy, alkylthio, cycloalkyl, benzyloxy or aryl, and which furthermore optionally contains one of the following groups ##STR2## or is bridged by an alkanediyl group andB, B' and G have the meaning given in the description,process for their preparation and their use as agents for controlling pests, and herbicides.

Abstract: The invention relates to novel thiophene derivatives of the formula (I) ##STR1## in which X represents halogen, alkyl, alkoxy, alkylthio, halogenoalkyl, halogenoalkoxy, nitro or cyano, or two substituents X, together with the carbon atoms to which they are attached, form a saturated or unsaturated, optionally substituted ring,n represents a number from 1 to 3, andZ represents one of the groups ##STR2## in which A, B, D, G, have the meaning given in the description, to processes for their preparation and to their use as pesticides and herbicides.

Abstract: The amide derivative of the present invention is one represented by the following general formula (I) and the dermatologic preparation of the present invention is one containing said amide derivative. ##STR1## wherein R.sup.1 represents a straight-chain or branched, saturated or unsaturated hydrocarbon group carrying 10 to 40 carbon atoms; R.sup.2 represents a straight-chain or branched, saturated or unsaturated hydrocarbon group carrying 3 to 39 carbon atoms; R.sup.3 represents a group containing at least one group represented by the formula: ##STR2## wherein R.sup.4 and R.sup.5 each represents a hydrogen atom or a straight-chain or branched or cyclic, saturated or unsaturated hydrocarbon group, or R.sup.4 and R.sup.

Abstract: An expedient synthesis of 4-(6-methoxynaphth-2-yl)-2-butanone is carried out by reacting 2-bromo-6-methoxynaphthalene with 3-ethylenedioxybutene in the presence of PdCl.sub.2 and triphenylphosphine, hydrogenating the 6-methoxy-2-(3-ethylene-dioxybuten-1-yl)naphthalene obtained and then hydrolysing the latter with an acid.

Abstract: A process to make .alpha.,.alpha.-difluoro-.beta.-hydroxy thiol esters of formula (IIIA) ##STR1## comprising reacting a difluoroethanethioate of formula (IVA) ##STR2## with a second reactant selected from the group consisting of aldehydes, ketones, acid halides and esters; in a solvent and in the presence of a strong base; with the proviso that the process is conducted in the absence of a catalyst and in the absence of a silyl containing compound. These thiol esters are useful as intermediates in organic syntheses of pharmaceutical products.

Abstract: Diphenylheteroalkyl derivatives of the formula I ##STR1## where A and R.sup.1 -R.sup.6 have the meanings specified in the description, and the preparation thereof are described.The substances are suitable for controlling diseases and as cosmetic agents.

Abstract: Disclosed are a process and intermediates of the formulae ##STR1## wherein X.sup.- is halide, BF.sub.4.sup.-, R.sup.3 SO.sub.3.sup.-, wherein R.sup.3 is C.sub.1 -C.sub.6 alkyl, CF.sub.3, C.sub.1 -C.sub.6 alkylphenyl or phenyl, and Q is a group of the formula ##STR2## wherein R is C.sub.1 -C.sub.6 alkyl; useful for preparing benzazepine intermediates of the formula ##STR3## These benzazepine intermediates are useful for preparing benzazepines having activity as selective D1 receptor antagonists.

Abstract: Compounds of the formula ##STR1## in which R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are as defined in claim 1 can be used as agrochemical active ingredients and can be prepared in a manner known per se.

Abstract: The amide derivative of the present invention is one represented by the following general formula (II) and the dermatologic preparation of the present invention is one containing said amide derivative. ##STR1## wherein R.sup.11 represents a straight-chain or branched hydrocarbon group carrying 10 to 40 carbon atoms; R.sup.12 represents a straight-chain or branched hydrocarbon group carrying 1 to 39 carbon atoms; R.sup.13 represents a hydrogen atom or a hydrocarbon group carrying 1 to 6 carbon atoms; and R.sup.14 represents a hydrogen atom or a hydrocarbon group having a straight-chain, branched or cyclic structure and carrying 1 to 40 carbon atoms which may contain an oxygen atom.

Abstract: Abstract of the Disclosure: Diphenylheteroalkyl derivatives of the formula I ##STR1## where A and R.sup.1 -R.sup.6 have the meanings specified in the description, and the preparation thereof are described.The substances are suitable for controlling diseases and as cosmetic agents.

Abstract: Disclosed herein is a process wherein glycerol, glycidol or 2,2-dimethyl-1,3-dioxolane-4-methanol is polymerized in the presence of an acid zeolite having an average pore size of at least 0.6 nanometer at 150.degree.-250.degree. C. At least 50 wt. % of cyclic polymers are obtained.

Abstract: The invention relates to new thermoprocessable copolymers of tetrafluoroethylene constituted by perfluoromethylvinylether (0.5-13% by weight), a fluorinated dioxole (0.05-3%) and tetrafluoroethylene (difference to 100%), particularly useful for coating electric cables by melt extrusion.It relates also to new perfluorodioxoles of formula ##STR1## wherein R.sub.F is a C.sub.1 -C.sub.5, perfluoroalkyl radical; X.sub.1 and X.sub.2 are, independently from each other, F or CF.sub.3 ; and their homopolymers and copolymers, in particular thermoprocessable copolymers as defined above.

Abstract: The invention describes the synthesis and use of photoactivated (or caged) fluorescent dyes. Upon illumination at less than about 400 nm the caged dyes release highly fluorescent, water soluble hydroxypyrenesulfonic acid dyes according to the following equation: ##STR1## X, Y, and Z are independently sulfonic acid, a sulfonic acid salt, a hydroxyl group, or hydrogen, with at least one of X, Y, and Z being a sulfonic acid or sulfonic acid salt. LINK is either an ether linkage or a carbonate linkage. BLOCK is a caging group whose photolysis results in liberation of a free hydroxypyrenesulfonic acid dye.The caged fluorescent dyes are useful for application in aqueous solutions, including fluids of biological origin. The caged dyes of the present invention are especially useful for flow tagging velocimetry.

Abstract: Provided by the present invention is a process for the biocatalytic synthesis of optically pure sphingosines from achiral starting material. The stereoisomers of sphingosine are prepared from chiral arene diols using stereospecific reaction techniques to obtain the desired sphingosine or derivative thereof.

Abstract: This invention offers novel compounds of the formula [I] which are useful for treatment of various immune diseases such as immunodeficiency and autoimmune diseases caused by immuno disorders, and synthetic intermediates thereof represented by the formula [II], ##STR1## wherein X is oxygen or NR.sup.7 and the R.sub.1 -R.sub.7 groups are defined in the specification.

Abstract: Compounds of formula ##STR1## Ar is optionally substituted phenyl, furyl, pyridyl, or thienyl; Y is selected from hydrogen, halogen, cyano, alkyl, haloalkyl, alkoxy, and alkoxycarbonyl; L is selected from ##STR2## and R.sup.1 and R.sup.2 are alkyl or together define a group of formula ##STR3## are potent inhibitors of lipoxygenase enzymes and thus inhibit the biosynthesis of leukotrienes. These compounds are useful in the treatment or amelioration of allergic and inflammatory disease states.

Abstract: Dermatological and/or cosmetological compositions containing at least one retinoid of general formula (I), ##STR1## and the use of such compounds for preparing dermatological and/or cosmetological compositions.

Abstract: Fluorinated alkene compounds useful for and methods of controlling nematodes, insects, and acarids that prey on agricultural crops. Polar compounds, for example, 3,4,4-trifluoro-3-butene-1-amine or 3,4,4-trifluoro-3-butenoic acid, are particularly useful for systemic control of pests. Novel method and intermediates for the preparation of 3,4,4-trifluoro-3-butene-1-amine are also provided.

Abstract: The novel 2R,4S-2-ethyl-4-[(4-phenoxyphenoxy)methyl]dioxolan of formula I ##STR1## can be used as a pesticide. It is used to control especially insects in fruit and citrus crops.

Abstract: Alcohols of the formula ##STR1## wherein R.sup.1 and R.sup.2 are each independently methyl or ethyl or together signify pentamethylene, formed by the enzymatic hydrolysis of a corresponding (RS) alkanoic acid ester are intermediates for Vitamin E.

Abstract: The novel 2R,4S-2-ethyl-4-[(4-phenoxyphenoxy)methyl]dioxolan of formula I ##STR1## can be used as a pesticide. It is used to control especially insects in fruit and citrus crops.

Abstract: Retinold-like activity is exhibited by compounds of the formula ##STR1## where X is S, O; R.sub.1, R.sub.2 and R.sub.3 are hydrogen or lower alkyl; R.sub.4 and R.sub.5 are hydrogen or lower alkyl with the proviso that R.sub.4 and R.sub.5 cannot both be hydrogen, R.sub.6 is hydrogen, lower alkyl, lower alkenyl, lower cycloalkyl or halogen; n is 0-5, and B is H, --COOH or a pharmaceutically acceptable salt, ester or amide thereof, --CH.sub.2 OH or an ether or ester derivative, or --CHO or an acetal derivative, or --COR.sub.1 or a ketal derivative where R.sub.1 is --(CH.sub.2).sub.m CH.sub.3 where m is 0-4, or a pharmaceutically acceptable salt thereof.

Abstract: Described is a process for the preparation of compositions of matter containing octalactones defined according to the structure: ##STR1## which includes the stereoisomers having the structures: ##STR2## by means of the sequential steps of (i) fermentation of caprylic acid or the ethyl ester of caprylic acid defined according to the generic structure: ##STR3## wherein R is hydrogen or ethyl using a microorganism selected from the group consisting of:Mortierella ramanniana var. ramanniana--CBS 112.08Mortierella ramanniana var. ramanniana--CBS 478.

Abstract: A process for the selective dehalogenation in position 5 of the naphthalenic nucleus of compounds of formula ##STR1## (wherein X, X.sub.1 and R have the meanings reported in the description) by treatment with a dehalogenating agent selected among hydrogen sulfide, aliphatic thiols or mixtures thereof in an inert anhydrous solvent at acid pH.

Abstract: New intermediates and processes for the preparation of vitamins A and E, which are the acetals of 5,6-dihalo-3-methyl-3-hydroxyhexanal or of 6-halo-3-hydroxy-3-methyl-5-hexenal or 3-methyl-3-hydroxy-5-hexenal, as well as processes for making the intermediates. After dehydrohalogenation and dehydration these intermediates are condensed directly with .beta.-ionone or with 2-methyl-2-heptene-6-one to synthesize vitamins A and E respectively.

Abstract: The present invention provides an optically active 2-methylenepentane derivative represented by the general formula ##STR1## (wherein R.sup.1 is a protective group for hydroxyl, R.sup.3 is a protective group for hydroxyl, X is a halogen atom or R.sup.4 SO.sub.3 group (wherein R.sup.4 is an alkyl or an aryl), and the symbol * represents an asymmetric carbon atom).

Abstract: This invention relates to a process for preparing 1,3-dioxolanes of formula: ##STR1## wherein; X.sub.1, X.sub.2, X.sub.3 and X.sub.4, like or different from one another, represent F, Cl, Br, I, CF.sub.2 OSO.sub.2 F, SO.sub.2 F, C(O)F, H, perhaloalkyl or oxyperhaloalkyl radicals containing from 1 to 5 carbon atoms,X.sub.5 and X.sub.6, like or different from each other, represent F or CF.sub.3. Said process is characterized in that a bis(fluoroxy)perfluoroalkane is reacted, at a temperature ranging from -140.degree. C. to +60.degree. C., with a halogenated olefin.This invention also relates to new 1,3-dioxolanes of formula (I) belonging to the class defined hereinbefore.

Abstract: Mixed cyclic acrolein glycerol acetals can be obtained by reacting acrolein with glycerol in the presence of a solid acidic catalyst and by a distillation workup in a higher space-time yield and in very high selectivity in comparison to the state of the art if the reaction is carried out in the presence of the reaction mixture as solvent, which mixture consists essentially of acrolein, glycerol, cyclic acrolein glycerol acetals and water, and in the absence of heterogeneous solvents and, to the extent necessary, the reaction mixture freed of catalyst is compounded prior to being worked up by distillation with such an amount of pH-increasing substance that it exhibits a pH in a range of 4.5 to 7 in tenfold dilution with water. The reaction preferably takes place at 10.degree. to 30.degree. C. using strongly acidic organic or inorganic ion exchangers.

Abstract: An asymmetric process for the preparation of enantiomerically pure .beta.-D-(-)-dioxolane-nucleosides. The enantiomerically pure dioxolane nucleosides are active HIV agents, that are significantly more effective than the prior prepared racemic mixtures of the nucleosides. The anti-viral activity of the compounds is surprising in light of the generally accepted theory that moieties in the endo conformation, including these dioxolanes, are not effective antiviral agents. The toxicity of the enantiomerically pure dioxolane nucleosides is lower that that of the racemic mixture of the nucleosides, because the nonnaturally occurring .alpha.-isomer is not included.The product can be used as a research tool to study the inhibition of HIV in vitro or can be administered in a pharmaceutical composition to inhibit the growth of HIV in vivo.

Abstract: The derivatives of the formula: ##STR1## wherein: R.sub.1 is H or C.sub.1 -C.sub.4 alkyl;X is an oxygen atom, a methylene group or a --CH.dbd.CH-- group;n is 1 or 2 when X is an oxygen atom or a methylene group and 0 or 1 when X is a --CH.dbd.CH-- group;D is an oxygen atom or a NOR group, wherein R.dbd.H or C.sub.1 -C.sub.4 alkyl;R.sub.3 is a C.sub.1 -C.sub.4 alkyl, C.sub.3 -C.sub.7 cycloalkyl, phenyl or benzyl group;each of R.sub.2 and R'.sub.2 independently is a hydrogen atom or a C.sub.1 -C.sub.4 alkyl, C.sub.3 -C.sub.7 cycloalkyl, phenyl or benzyl group; andR'.sub.2 and R.sub.3 may further form together a --(CH.sub.2).sub.3 -- or --(CH.sub.2).sub.4 -- chain,useful as drugs.

Abstract: A retroviral protease inhibiting compound of the formulaA--X--Bor a pharmaceutically acceptable salt, prodrug or ester thereof, wherein X is a linking group; A is(1) substituted amino,(2) substituted carbonyl,(3) functionalized imino,(4) functionalized alkyl,(5) functionalized acyl,(6) functionalized heterocyclic or(7) functionalized (heterocyclic)alkyl; and B is(1) substituted carbonyl independently defined as herein,(2) substituted amino independently defined as herein,(3) functionalized imino independently defined as herein,(4) functionalized alkyl independently defined as herein,(5) functionalized acyl independently defined as herein,(6) functionalized heterocyclic independently defined as herein or(7) functionalized (heterocyclic)alkyl independently defined as herein.