Abstract: The present invention relates to a method for the treatment of cognitive disorders such as alzheimer disease and to a compound for use in such method.

Abstract: The invention is directed to a method of killing or inhibiting the growth of the malaria-causing pathogen Plasmodium falciparum by exposing the pathogen to an effective amount of a preparation comprising a compound selected from the group consisting of:a) a compound of formula I: ##STR1## where ##STR2## b) a compound of formula II; ##STR3## where each R' is --H or each R' is --OH; and c) a compound of formula III; ##STR4## where R" is --NH.sub.2, --H, or --SO.sub.3 M, and where M is H, Na, or K.

Abstract: A compound of the following structure: ##STR1## wherein, when R.sub.8 =H: R.sub.1 =alkyl, cycloalkyl, arylalkyl, aryl;R.sub.2 =cycloalkyl, aryl, C.sub.3 -C.sub.10 alkyl;X,Y=O, S(O).sub.n, NH;Z=CHO, CO.sub.2 R.sub.3, CONHR.sub.4 R.sub.5, CN, COR.sub.6, H, halo, HCN, NHCONR.sub.4 R.sub.5, CONR.sub.4 OR.sub.5, CONR.sub.4 NR.sub.5 R.sub.6, 1-tetrazole, S(O).sub.n OH, S(O).sub.n NR.sub.3 R.sub.4, C.dbd.NOH, C(.dbd.N(OH)NH.sub.2, OCONR.sub.7 R.sub.6, P(O)(OR.sub.4).sub.2, C(.dbd.N(YR.sub.3))R.sub.4, NH.sub.2, SH, OH, OS(O).sub.2 R.sub.3, C(.dbd.NYC(.dbd.O)R.sub.3)R.sub.4, C(O)CO.sub.2 R.sub.3, C(O)CONR.sub.3 R.sub.4, CH(OH)CO.sub.2 R.sub.3, CHFCO.sub.2 R.sub.3, CF.sub.2 CO.sub.2 R.sub.3, CH(OH)CONR.sub.3 R.sub.4, CF.sub.2 CONR.sub.3 R.sub.4, C.dbd.NNH.sub.2, C(.dbd.NOC(.dbd.O)R.sub.3)R.sub.4, C(.dbd.NNHC(.dbd.O)R.sub.3)R.sub.4, C(.dbd.NOH)R.sub.3, C(.dbd.NNR.sub.3)R.sub.4, NHC(.dbd.O)R.sub.6 or C(O)CONH.sub.2 ;R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.

Abstract: A method of reducing the severity of toxoplasmosis resulting from infection of a patient with Toxoplasma gondii by administering to a patient in need of such treatment, either after infection or before exposure to infection, a therapeutically effective amount of a compound that is a spiropiperidyl derivative of rifamycin S, wherein the derivative comprises an imidazole ring that includes carbons at positions 3 and 4 of the rifamycin ring, the carbon at position 2 of the imidazole ring also being a ring carbon at position 4 of a piperidine ting system, thereby forming a spiropiperidyl ring system, the spiropiperidyl ring system optionally comprising a lower hydrocarbon substituent on the nitrogen of the piperidine.

Abstract: The invention provides a composition for the treatment for the hair, scalp and skin to improve condition and to assist in hair regrowth which comprises a pharmaceutically acceptable oxalate of a group Ia or Ia or ammonium oxalate metal disposed in a pharmaceutically acceptable carrier of diluent therefor. Preferably, the group IIa metal is calcium and the pharmaceutically acceptable carrier or diluent is an ointment.

Abstract: This invention relates to benzyl and naphthalenylmethyl thiophenones and cyclopentenones, some of which are novel, which have oral antihyperglycemic activity in diabetic mice, a genetic animal model of non-insulin dependent diabetes mellitus. These compounds are represented by the formula ##STR1## wherein: R.sup.2 and R.sup.3 are independently selected from hydrogen, C.sub.1-6 alkyl, halogen, C.sub.1-6 alkoxy, thio-C.sub.1-6 alkyl, or trifluoromethyl or R.sup.2 together with R.sup.3 forms a benzo ring fused to the phenyl ring and optionally substituted with one or two substituents independently selected from C.sub.1-6 alkyl, halogen, C.sub.1-6 alkoxy, thio-C.sub.1-6 alkyl, or trifluoromethyl;R.sup.1 is selected from hydrogen, C.sub.1-6 alkyl, halogen, C.sub.1-6 alkoxy, thio-C.sub.1-6 alkyl, or trifluoromethyl; andR.sup.4 is selected from the group consisting of: ##STR2## wherein R.sup.5 is H or C.sub.1-6 alkyl or a pharmaceutically acceptable salt thereof.

Abstract: The present invention relates to the use of 2-[4-(4-chlorophenyl)cyclohexyl]-3-hydroxy-1,4-naphthoquinone or a physiologically acceptable salt or other physiologically functional derivative thereof for the manufacture of a medicament for the treatment of tumours in animals, to pharmaceutical compositions for the treatment of tumours in animals, to pharmaceutical compositions for the treatment of tumours, comprising said compound as active ingredient and to a method of treating tumours in an animal which comprises administering to said animal an effective amount of said compound.

Abstract: The present invention relates to pharmaceutical compositions for the treatment of infections caused by Microsporidia comprising treating an animal with 2-[4-(4-chlorophenyl)cyclohexyl]-3-hydroxy-1,4-naphthoquinone or a physiologically acceptable salt thereof.

Abstract: The present invention relates to pharmaceutical compositions for the treatment and/or prophylaxis of protozoal infections caused by Kinetoplastida, Apicomplexa, Anaerobic protozoa and Mircosporidia comprising 2-[4-(4-chlorophenyl)cyclohexyl]-3-hydroxy-1,4-naphthoquinone or a physiologically acceptable salt or other functional derivative thereof as active ingredient and to a method of treating or preventing siad protozoal infections in an animal which comprises administering to said animal an effective amount of siad compound.

Abstract: Nabumetone which is spray-chilled and formulated into unit dose forms which have a smaller volume than was previously possible.

Abstract: The invention encompasses the novel compound of Formula I useful in the treatment of cyclooxygenase-2 mediated diseases. ##STR1## The invention also encompasses certain pharmaceutical compositions for treatment of cyclooxygenase-2 mediated diseases comprising compounds of Formula I.

Abstract: Diaromatic compounds, characterized in that they correspond to the following general formula: ##STR1## in which: R.sub.1 is --CH.sub.3, --CH.sub.2 OH, --COR.sub.8 or --CH.sub.2 OCOR.sub.9, R.sub.8 is H, OH, --OR.sub.10, --N(rr') or alkyl, R.sub.10 is alkyl, alkenyl, aryl or aralkyl, r and r' being H, alkyl, aryl, aralkyl, etc., r and r' together form a heterocycle, R.sub.9 is alkyl, alkenyl or a sugar residue, R.sub.2 and R.sub.3 are --OR.sub.11 or --OCOR.sub.11, R.sub.11 is H, alkyl, fluoroalkyl, aryl or aralkyl, R.sub.3 in addition being H, R.sub.4 is H, OH, alkyl, alkoxy, F, Cl or --CF.sub.3, R.sub.5 and R.sub.7 are H, OH, alkoxy, .alpha.-substituted alkyl or .alpha.,.alpha.'-disubstituted alkyl, etc., R.sub.6 is H, OH, alkyl, alkoxy, cycloalkyl, etc., R.sub.5 and R.sub.7 cannot simultaneously be OH or alkoxy and R.sub.4, R.sub.5, R.sub.6 and R.sub.7 cannot simultaneously be H, R.sub.5 and R.sub.6 or R.sub.6 and R.sub.

Abstract: Compounds useful as antiviral agents against DNA-containing viruses, such as herpes group viruses, are disclosed. The compounds are represented by Formula 1.0: ##STR1## and their pharmaceutically acceptable salts and solvates; wherein:(A) X is selected from the group consisting of N--R.sup.3, O, S, and C(R.sup.3).sub.2 ;(B) R.sup.3 is selected from H and a range of substituents;(C) R.sup.1 is an etherifying or esterifying group;(D) R.sup.2 is selected from a range of substituents;(E) m is 0 or an integer from 1 to 4; and(F) R.sup.4 and R.sup.5 are the same and are selected from alkyl and acyl groups;together with the pharmaceutically acceptable salts of the compounds of Formula 1.0 that are acidic or basic.Pharmaceutical compositions containing compounds represented by Formula 1.0 are disclosed. Also disclosed are methods of treating a viral infection using compounds represented by Formula 1.0.

Abstract: Compounds useful as antiviral agents against DNA-containing viruses, such as herpes group viruses, are disclosed. The compounds are are represented by compounds of Formula 1.0: ##STR1## and their pharmaceutically acceptable salts and solvates. Pharmaceutical compositions containing compounds represented by Formula 1.0 and methods of treating a viral infection using compounds represented by Formula 1.0 are disclosed.Also disclosed are compounds useful as antihypertensive agents and methods of treating hypertension using such compounds. The antihypertensive agents are compounds represented by Formula 1.0 wherein R.sup.4 is selected from the group consisting of alkyl and aminoalkyl. Preferably R.sup.1 is H.

Abstract: A method for treating or preventing a Pneumocystis carinii infection in a mammal by administering a certain naphthoquinone compound or physiologically acceptable salts thereof.

Abstract: Certain spirocyclic heterocyclic compounds, and their pharmaceutically-acceptable salts, are inhibitors of the aldose reductase enzyme, and so are useful for the control of diabetic complications.

Abstract: The present invention relates to the treatment and prophylaxis of Pneumocystis carinii infections with 2-[4-(4-chlorophenyl)cyclohexyl-3-hydroxy-1,4-naphthoquinone.

Abstract: Compounds useful as antihypertensive agents, or antiviral agents against DNA containing viruses, such as herpes group viruses, are disclosed. The compounds are represented by Formula 1.0: ##STR1## and their pharmaceutically acceptable salts and solvates. Pharmaceutical compositions containing compounds represented by Formula 1.0 are disclosed. Also disclosed are methods of treating hypertension or a viral infection using compounds represented by Formulas 1.0.Also disclosed is a compound of Structure B ##STR2## useful as an intermediate in producing compounds of Formula 1.0. A process for preparing the compounds of Formula 1.0 is also disclosed. In the process a compound of Structure B ##STR3## is reacted with an alkoxide R.sub.1 O.sup.- M.sup.+ in a solvent comprising the corresponding alcohol R.sub.1 OH of the alkoxide. Optionally, an organic cosolvent may be used with the solvent.

Abstract: 3-Oxo-4-acyl or carbamyl-bicyclic aromatic and heterocyclic compounds as inhibitors of cyclooxygenase and lipoxygenase and useful as antiallergy and antiinflammatory agents.

Abstract: A 5,6,7,8-tetrahydro-1-naphthalenol derivative of the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 represent lower alkyl,R.sub.5 and R.sub.6 represent hydrogen or lower alkyl,R represents hydrogen, C.sub.1 -C.sub.18 alkyl, C.sub.2 -C.sub.18 alkyl substituted by one or more hydroxyl groups, C.sub.3 -C.sub.18 alkenyl, C.sub.2 -C.sub.18 acyl, benzyl, benzoyl, carboxyl and carboxylic salts of an alkali or alkaline earth metal or of an organic amine.The derivative is useful as an antioxidant in cosmetic compositions and in pharmaceutical compositions for the preventive treatment of cutaneous inflammations and allergies or certain forms of cancer.

Abstract: The present invention discloses the antimicrobial utility of certain iodonium ylide compounds. The particular iodonium ylide compounds are phenyl iodonium ylides having an ortho substituent that stabilizes the positive charge on the polyvalent iodine by a nonbonded electrostatic interaction. The polyvalent iodine is further stabilized by a cyclic 1,3-dicarbonyl anion.

Abstract: A benzonaphthalene compound has the formula ##STR1## wherein R.sub.1 represents ##STR2## or (ii) --CH.sub.2 OH; R.sub.6 represents ##STR3## or OR.sub.7 wherein R.sub.7 represents hydrogen, alkyl having 1-20 carbon atoms, monohydroxyalkyl or polyhydroxyalkyl, r' or r" represent hydrogen, lower alkyl, mono or polyhydroxyalkyl, aryl or a residue of an amino acid or a sugar, or together form a heterocycle; R.sub.2 represents hydrogen, alkyl having 1-15 carbon atoms, alkoxy having 1-4 carbon atoms or a cycloaliphatic radial; R.sub.3 represents hydrogen, hydroxy, alkyl having 1-4 carbon atoms, alkoxy having 1-10 carbon atoms, a cycloaliphatic radical, a thiocycloaliphatic radical or --O--Si(CH.sub.3).sub.2 --R.sub.8 wherein R.sub.8 represents lower alkyl; and R.sub.4 and R.sub.5 represent hydrogen, lower alkyl, hydroxy or lower acyloxy.This compound is useful in the topical and systemic treatment of dermatologic diseases and in the treatment of the degeneration of conjunctive tissues.

Abstract: Certain 2-naphthyl ketones are used as inhibitors of cholesterol esterase and function as hypolipidemic and hypocaloric agents. The invention also relates to a method of decreasing the absorption of dietary cholesterol and fats through the wall of the intestinal tract.

Abstract: The fermentation of a fungal organism identified as Chrysosporium meridarium produces a novel binaphthalene compound which is a highly potent antiparasitic, insecticidal, and anthelminthic agent.

Abstract: The invention relates to benzylketone phospholipase A.sub.2 inhibitors, pharmaceutical compositions containing them, and methods of treating phospholipase A.sub.2 -mediated conditions in mammals by administration of a therapeutically effective amount of such a benzylketone phospholipase A.sub.2 inhibitor. These compounds are also intermediates in the synthesis of other PLA.sub.2 inhibitors.

Abstract: Novel combinations of an antiprotozoal naphthoquinone and a 4-pyridinol or an alkanoic ester thereof wherein the antiprotozoal activity of the combination is potentiated with respect to the corresponding activity of the components of the combination. The combinations are especially useful for the treatment or porphylaxis of malaria.

Abstract: Novel antiprotozoal naphthoquinones having the general formula ##STR1## (wherein either R.sup.1 is hydrogen and R.sup.2 is selected from C.sub.1-6 alkoxy, aralkoxy, C.sub.1-6 alkyl-C.sub.1-6 alkoxy, phenyl substituted by one or two groups selected from halogen and C.sub.1-6 alkyl, halogen and perhalo-C.sub.1-6 alkyl; or R.sup.1 and R.sup.2 are both C.sub.1-6 alkyl or phenyl; and n is 0 or 1) and salt thereof. The compounds of formula (I) are useful for the treatment or prophylaxis of protozoal diseases including malaria, theileriosis and coccidiosis. Various processes for preparing compounds of formula (I) are described.

Abstract: A drug composition for the local treatment of alopecia areata and other dermatological diseases is disclosed. The composition contains as an active ingredient an aliphatic, alkoxy or aryl substituted cyclopropenone. Diphenylcyclopropenone is a particularly preferred representative cyclopropenone useful in the context of the present invention.

Abstract: A method and certain compositions for treating Pneumocystis carinii infections in a mammal by administering a certain naphthoquinone compound or physiologically acceptable salts thereof.

Abstract: A method of combating agricultural pest comprising applying a pesticidally effective amount of a substituted 1,4-naphthoquinone on agricultural pests and/or their environment, said 1,4-naphthoquinone being of the formula ##STR1## in which n represents the number zero or a number from 1 to 12,R.sup.1 represents hydrogen, t-butylcarbonyl or acetyl andR.sup.2 represents phenyl which is substituted by bromine, fluorine, chlorine, trifluoromethyl, trifluoromethoxy, trifluoromethylsulphenyl, trifluoromethylsulphonyl or trimethylsilyl or cyclohexyl which is substituted by methyl, trifluoromethyl or trimethylsilyl orR.sup.2 represents C.sub.1 -C.sub.8 -alkyl which is substituted by fluorine, chlorine or bromine.

Abstract: A pharmaceutical composition, comprising: Coenzyme Q.sub.10 (ubidecarenone) 2-17% by weight; Lecithin 50-70% by weight; Surfactant agent 20-48% by weight. The surfactant agent has a melting point comprised between 35.degree. and 55.degree. C. and a HLB value from 12 to 15. Said composition provides a high absorption of Coenzime Q.sub.10. Solid pharmaceutical preparations containing the above composition are described too.

Abstract: Three naphthoquinones isolated from cultures of Fusarium solani were found to be effective antibiotics against gram-positive bacteria. Controlling the dissolved oxygen concentration in the fermentation medium between 0.7 and 2.0 ppm resulted in maximum yields of the naphthoquinones. 2,3-Dihydro-5,8-dihydroxy-6-methoxy-2-hydroxymethyl-3-(2-hydroxypropyl)-1, 4- naphtholenedione was the most effective antibiotic.

Abstract: There are provided new alkane and alkoxyalkane derivatives of the general formula I ##STR1## in which R.sub.1, R.sub.2, R.sub.3, R.sub.4 and A have the meanings given in the description, processes for their preparation and insecticidal and acaricidal compositions containing these compounds.

Abstract: Tetralin derivatives of the formula I ##STR1## where X, R.sup.1, R.sup.2 and R.sup.3 have the meanings stated in the description, and their preparation are described. The novel compounds are useful for the treatment of disorders.

Abstract: A food composition for poisoning a rodent, which comprises a rodent foodstuff which contains as an active rodenticidal agent, a lethal or sub-lethal quantity of a compound having the formula: ##STR1## wherein X is Cl, Br, F, or I; Y is H, Cl, Br, F, I, --SO.sub.3 H, SO.sub.3 Na, or --SO.sub.3 K; and R.sub.1 -R.sub.4 are each independently H, Cl, Br, F, I, C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxyl, or C.sub.1 -C.sub.6 alkoxyalkyl or a hydroquinone analogue of the compound, and a method for controlling rodents using said composition.

Abstract: A compound of formula IIR.sub.A CH.sub.2 COCHDR.sub.bin which formula:R.sub.A represents a group ArCR.sub.1 R.sub.2 -- in which Ar represents a phenyl or naphthyl group optionally substituted by one or more halogen, alkoxy, haloalkoxy, methylenedioxy or C.sub.1 -C.sub.6 alkyl or haloalkyl groups;R.sub.1 and R.sub.2 together with the carbon to which they are attached jointly represent a C.sub.3 -C.sub.6 cycloalkyl group optionally substituted by one or more halogen atoms or C.sub.1 -C.sub.6 cycloalkyl groups andR.sub.B represents the residue of an alcohol R.sub.B CHDOH in which D is hydrogen or cyano and of which the [IR, cis]2,2-dimethyl-3-(2,2-dibromovinyl)cyclopropane carboxylic ester is signficantly insecticidal.

Abstract: Tetrahydronaphthalene derivatives of the formula ##STR1## wherein Y, m, n, R and R.sup.1 to R.sup.9 are as set forth herein, are described.These compounds have a pronounced calcium-antagonistic and anti-arrhythmic activity and can accordingly be used as medicaments, especially for the control or prevention of angina pectoris, ischaemia, arrhythmias and high blood pressure. The compounds of formula I can be prepared by the amination of a compound of the formula ##STR2## with a corresponding N-methyl-phenylalkylamine and optional subsequent O-acylation. Compounds of formula II and IV are also described and are within the scope of the invention.

Abstract: Pharmaceutical compositions with comprise a compound of the formula (I): ##STR1## wherein X is a chlorine or bromine atom or a methoxyl, methylthio or alkyl group of 1-4 carbon atoms; Y is a --CHR.sub.1 --CH.sub.2 -- or --CR.sub.1 .dbd.CH-- group where R.sub.1 is a hydrogen atom or a methyl group and A is a CHOH or CO group, and a pharmaceutically acceptable carrier selected from the group of creams, ointments, lotions, gels, aerosols, sprays, liniments and gel sticks. The compositions possess systemic anti-inflammatory activity when administered topically.

Abstract: New tropolone derivatives of the general formula: ##STR1## wherein R.sup.1 represents H or an alkyl group, R.sup.2 represents an alkyl, aryl, aralkyl or heterocyclic group and R.sup.3 represents an alkoxyl, aryl or heterocyclic group or a group of the formula: ##STR2## or R.sup.2 and R.sup.3 may form together a part of a heterocyclic group, their metal complex salts, processes for the preparation thereof and the use thereof as anti-tumor agents.

Abstract: This invention relates to pharmaceutical compositions containing a class of 5-phenyl-1,3-dioxoalkenyl compounds useful as inhibitors of leukotriene biosynthesis and thus useful in the treatment of conditions associated with leukotrienes. This invention also relates to the use of the 5-phenyl-1,3-dioxoalkenyl compounds in the inhibition of leukotriene biosynthesis and thus in the treatment of conditions associated with leukotrienes. This invention further relates to a novel process for the preparation of the 5-phenyl-1,3-dioxoalkenyl compounds.

Abstract: New compounds of the formula ##STR1## in which R.sub.1 is an allylamino, acetylamino or propionylamino radical,R.sub.2 is hydrogen or a 2-methoxyethoxy or ethoxy radical,R.sub.3 is hydrogen or a sulphamoyl radical, andR.sub.4 is hydrogen,and of the formula ##STR2## in which R.sub.1 is a halogen atom or a free or substituted hydroxyl, sulphhydryl or amino group,R.sub.2 is a hydrogen atom, an alkyl radical, a halogen atom, or a free or substituted hydroxyl, sulphhydryl or amino group,R.sub.3 and R.sub.4 each independently is hydrogen, alkyl, hydroxyl, alkoxy, sulphonamido or halogen, with the proviso that R.sub.2, R.sub.3 and R.sub.4 are hydrogen when R.sub.1 is hydroxyl,exhibit anti-inflammatory activity.

Abstract: This invention relates to novel compounds having pharmaceutical activity and having the general structure ##STR1## wherein the Z, R.sub.1, R.sub.2, R.sub.3, R.sub.4, n and m are defined within.

Abstract: A method of treating diabetes mellitus using arylglyoxals which are known compounds.

Abstract: The present invention relates to 2-arylethyl ether or thioether derivatives represented by the following general formula [I]: ##STR1## wherein Ar stands for an aryl group, R.sup.1 stands for straight or branched chain alkyl group of 1 to 6 carbons, R.sup.2 stands for a hydrogen atom, or a methyl or ethyl group, R.sup.3 stands for a halogen atom, or a methyl or methoxyl group, R.sup.4 stands for a hydrogen or halogen atom, or a lower alkyl or lower alkoxy group, and n is an integer of 1 or 2 with the proviso that when n is 2, the groups R.sup.4 may be the same or different, and Y stands for an oxygen or sulfur atom, and also to processes for the preparation of these ethers or thioethers and a use of these ethers or thioethers.These compounds of the present invention have excellent insecticidal and acaricidal activities while the toxicity of these compounds are very low.

Abstract: The compound of the formula: ##STR1## wherein R.sub.1 is hydrogen, methyl or hydroxymethyl, R.sub.2 is hydrogen or methoxy, R.sub.3 is hydroxy or methoxy, and R.sub.4 is hydrogen or a group ##STR2## is novel, and the compound is of use as inhibitors of animal tissue fibrosis, or biochemical reagents.

Abstract: The invention relates to contraceptive vaginal tablets as well as to a process for preparing them. The tablets of the invention have the following composition:0.2 to 3 parts by weight of boric acid,10 to 20 parts by weight of tartaric acid,1 to 2 parts by weight of vitamin K.sub.3 -sodium bisulfite adduct,0.8 to 1.2 parts by weight of polyvinyl pyrrolidone,2 to 5 parts by weight of magnesium stearate,8 to 12 parts by weight of carboxymethyl cellulose,8 to 12 parts by weight of lactose and50 to 65 parts by weight of microcrystalline cellulose.The vaginal tablets contain preferably 5 to 10 mg of vitamin K.sub.3 -sodium bisulfite adduct and have a total weight of 500 mg.The tablets of the invention are prepared preferably in such way that the boric acid, the tartaric acid and the vitamin K.sub.

Abstract: The compound of the formula: ##STR1## wherein R.sub.1 is hydrogen, methyl or hydroxymethyl, R.sub.2 is hydrogen or methoxy, R.sub.3 is hydroxy or methoxy, and R.sub.4 is hydrogen or a group ##STR2## is novel, and the compound is of use as inhibitors of animal tissue fibrosis, or biochemical reagents.

Abstract: A benzonaphthalene compound has the formula ##STR1## wherein R.sub.1 represents ##STR2## or (ii) --CH.sub.2 OH; R.sub.6 represents ##STR3## or OR.sub.7 wherein R.sub.7 represents hydrogen, alkyl having 1-20 carbon atoms, monohydroxyalkyl or polyhydroxyalkyl, r' or r" represent hydrogen, lower alkyl, mono or polyhydroxyalkyl, aryl or a residue of an amino acid or a sugar, or together form a heterocycle; R.sub.2 represents hydrogen, alkyl having 1-15 carbon atoms, alkoxy having 1-4 carbon atoms or a cycloaliphatic radial; R.sub.3 represents hydrogen, hydroxy, alkyl having 1-4 carbon atoms, alkoxy having 1-10 carbon atoms, a cycloaliphatic radical, a thiocycloaliphatic radical or --O--Si(CH.sub.3).sub.2 --R.sub.8 wherein R.sub.8 represents lower alkyl; and R.sub.4 and R.sub.5 represent hydrogen, lower alkyl, hydroxy or lower acyloxy.This compound is useful in the topical and systemic treatment of dermatologic diseases and in the treatment of the degeneration of conjunctive tissues.