Abstract:
The invention relates to hydrolyzable and polyadditive silanes, a method ofheir production and of their use in the production of (hetero) silicic acid polycondensates and of polyadducts. The silanes in accordance with the invention have the general formula �(HS--R.sup.5).sub.n R.sup.6 --S--E--R.sup.5 !.sub.a SiX.sub.x R.sup.3.sub.4-a-x (I) in which the groups and indices are equal or different and have the following meaning: E=--CO--NH--, CS--NH--, --CH.sub.2 --CH.sub.2 -- or --CH.sub.2 --CH(OH)--; R.sup.3 =alkyl, alkenyl, aryl, alkylaryl or arylalkyl each with 1 to 15 carbon atoms, whereby these groups may be interrupted by oxygen or sulfur atoms, by ester, carbonyl, amide or amino groups; R.sup.5 =Alkene, arylene, arylenealkene or arylenealkene each with 1 to 15 carbon atoms, whereby these groups may be interrupted by oxygen or sulfur atoms, by ester, carbonyl, amide or amino groups; R.sup.6 =alkene, arylene, arylenealkene or arylenealkene each with 1 to 15 carbon atoms, whereby these groups may be interrupted by oxygen or sulfur atoms, by ester, carbonyl, amide or amino groups; X=hydrogen, halogen, hydroxy, alkoxy, acyloxy, alkylcarbonyl, alkoxycarbonyl or NR".sub.2 ; a=1, 2 or 3; n=2, 3, 4 or 5; x=1, 2 or 3.
Abstract:
Compounds of the formula ##STR1## wherein R.sub.1 is C.sub.3 -C.sub.8 cycloalkyl, halo-C.sub.3 -C.sub.8 cycloalkyl, C.sub.3 -C.sub.8 cycloalkyl-C.sub.1 -C.sub.6 alkyl, halo-C.sub.3 -C.sub.8 cycloalkyl-C.sub.1 -C.sub.6 alkyl, --Si(R.sub.3).sub.3, --S--R.sub.4, --SO.sub.2 --R.sub.6 or --CO--R.sub.9 ;R.sub.2 is halogen, C.sub.1 -C.sub.4 alkyl or CF.sub.3, the substituents R.sub.2 being identical or different when n is 2; R.sub.3 each independently of the others is C.sub.1 -C.sub.6 alkyl, halo-C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy or phenyl; R.sub.4 is aryl or heteroaryl each of which is unsubstituted or substituted; R.sub.6 is unsubstituted or substituted C.sub.1 -C.sub.10 alkyl, C.sub.2 -C.sub.6 alkenyl, C.sub.2 -C.sub.6 alkynyl, C.sub.1 -C.sub.20 -alkoxy, C.sub.2 -C.sub.6 alkenyloxy, C.sub.2 -C.sub.6 alkynyloxy, C.sub.1 -C.sub.4 alkylthio, aryl, aryloxy or arylthio, or is optionally substituted amino; R.sub.9 is hydroxy, unsubstituted or substituted C.sub.1 -C.sub.10 alkyl, C.sub.2 -C.sub.6 alkenyl, C.sub.2 -C.sub.6 alkynyl, C.sub.3 -C.sub.8 cycloalkyl, aryl or aryloxy, or is optionally substituted amino; R.sub.12 is hydrogen or unsubstituted or substituted C.sub.1 -C.sub.10 alkyl; m is 1,3,5,7,9 or 11; n is 0,1 or 2; X is fluorine or chlorine; and Y is hydrogen, fluorine or methyl; ps in free form or in salt form, can be used as pesticides and can be prepared in a manner known per se.
Abstract:
The organosilanes and organopolysiloxanes containing groups which form free radicals and are soluble in organic solvents, processes for their preparation, macromonomers and graft copolymers from the organosilanes and organopolysiloxanes according to the invention as free radical initiators and organic monomers which can be polymerized by free radicals, a process for the preparation of the macromonomers and graft copolymers and their use.
Abstract:
The present invention relates to novel piperidine compounds of the formula (I) ##STR1## in which A is e.g. a group of the formula ##STR2## where R.sub.4 is e.g. hydrogen or methyl, X.sub.3 is e.g. --O-- or --NH-- and R.sub.5 ' is e.g. ethylene, propylene or decamethylene, R.sub.1 is e.g. methyl, methoxy, ethoxy or OH, R.sub.2 and R.sub.3 are e.g. methyl, m+n is e.g. a number from 1 to 40, n varies e.g. from zero to 50% of the sum m+n, X.sub.1 is e.g. as defined for R.sub.1 or is a group (CH.sub.3).sub.3 SiO-- and X.sub.2 is e.g. hydrogen, methyl, ethyl, a group (CH.sub.3).sub.3 Si-- or a group ##STR3## and, when m+n is a number from 3 to 10, X.sub.1 and X.sub.2 together also form a direct bond. The compounds of the formula (I) are effective in stabilizing an organic material against thermal, oxidative and light-induced degradation.
Abstract:
This invention provides a purified retro-retinoid compound characterized by a molecular mass of about 302 daltons. Also provided by this invention is a method of enhancing the growth of a cell in a vitamin A reduced environment which comprises contacting the cell with an effective growth enhancing amount of a compound having a structure: ##STR1## wherein the configuration of the C6, C8, C10 and C12 double bond independently is Z or E and the absolute configuration at C-14 is independently R or S; wherein R.sub.1 is alkyl, alkyl halide, alcohol, ester, ether, aldehyde, ketone, carboxylic acid, carboxylic ester, acid halide, amide, nitrile, or amine; and wherein R.sub.2 is 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 R.sub.1 and R.sub.2 are replaced by a 14, 15-oxirane group; and wherein the retro structure is alpha or gamma. Further provided are a method for enhancing transcription of a gene regulated by retinoid in a cell, or a method for enhancing an immune response in a subject.
Abstract:
The present invention is concerned with the preparation of N-substituted vicinal aminoalcohol derivatives from the corresponding hydroxyl-protected cyanohydrin derivatives by successive partial reduction, transimination using a primary amine, reduction of the resulting imine and optional removal of the hydroxyl-protecting group. The products are obtained either as a racemate or in an optically pure form, depending upon the stereochemical composition of the starting cyanohydrin derivatives.The present invention is also concerned with certain new enantiomerically pure hydroxyl-protected vicinal aminoalcohols.
Abstract:
The present invention relates to a process for preparing (2-arylpropyl)alkylsilanes represented by the formula III by reacting (2-arylpropyl)silanes represented by the formula I with olefin compounds represented by the formula II in the presence of hydrosilation catalysts such as chloroplatanic acid, platinum on silica, tributylamine and Pd, Rh, Ni metals. ##STR1## Olefin compounds(cyclohexene or CH.sub.2 =CH--R.sup.3) (II) ##STR2## In the formulas (I) and (III), R.sup.1 and R.sup.2 represent independently hydrogen, alkyl(C.sub.1 -C.sub.4), fluoro, chloro or bromo; and Ar represents phenyl ring, naphthalene ring, or biphenyl ring. X represents hydrogen or chloro group. In the formula (III), R represents --(CH.sub.2 CH.sub.2)--R.sup.3, sec-butyl, or cyclohexyl wherein R.sup.3 =Ph, CH.sub.2 Cl, C.sub.n H.sub.2n CH.sub.3 (n=0-15), CH.sub.2 Si(Me).sub.m Cl.sub.3-m (m=O-3), (CH.sub.2).sub.2 Si(Me).sub.m (OMe).sub.3-m (m=O-3), (CH.sub.2).sub.3 Si(Me).sub.m (OMe).sub.3-m (m=O-3), Si(Me).sub.m Cl.sub.3-m (m=0-3), CF.sub.3, CN, CH.sub.2 CN, ##STR3## CH.dbd.CH.sub.2, (CH.sub.2 ).sub.4 CH.dbd.CH.sub.2, ##STR4## or Ph--CH.sub.2 Cl.
Abstract:
The present invention relates to a process for preparing 1,3-disilacyclotutanes by pyrolyzing alkoxytrisilaalkaness at a temperature of from 400.degree. C. to 800.degree. C. at the atmospheric pressure or under the vacuum. This is a new synthetic route of 1,3-disilacyclobutanes which employs readily available starting materials without using alkaline metals or magnesium, affords very good yields, produces very clean product mixtures separable by distillation, and tolerates functionality on silicon.
Abstract:
The present invention relates to a process for the preparation of (3R, 4S)-3-hydroxy-4-phenyl-2-azetidinone derivatives which are useful intermediates in the synthesis of taxol from baccatin III, said process comprises reacting an acyloxyacetyl halide with an imine derived from L-threonine; and to compounds of formula (III) which are produced in said process: ##STR1## wherein Ar is phenyl; R.sup.1 is hydrogen, an acyl radical of a carboxylic acid, or a carbonic acid ester radical; R.sup.2 is hydrogen or a carboxy protecting group; and R.sup.3 is hydrogen or a hydroxy protecting group.
Abstract:
Compounds of the formula Ib ##STR1## in which R.sub.1 and R.sub.2 independently of one another are linear or branched C.sub.1 -C.sub.12 alkyl, cycloalkyl having 5 to 8 ring carbon atoms, phenylalkyl having 1 to 4 C atoms in the alkylene group, the cyclic radicals being unsubstituted or substituted by C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.4 alkoxy, or R.sub.1 and R.sub.2 independently of one another are --SiR.sub.4 R.sub.5 R.sub.6 in which R.sub.4, R.sub.5 and R.sub.6 independently of one another are C.sub.1 -C.sub.12 alkyl, phenyl, benzyl, or phenyl or benzyl, each of which is substituted by C.sub.1 -C.sub.4 alkyl or C.sub.1 -C.sub.4 alkoxy, and R.sub.3 is a bridging member which, together with the radical --OCH--CH.sub.2 --CHO-- to which it is bonded, forms a 6- to 8-membered ring. These compounds are valuable intermediates for the preparation of carbacyclic nucleosides of the natural and unnatural series and of the racemates.