35975-12-3

Advances in catalysis have enabled the ring-opening copolymerization of epoxides and cyclic anhydrides to afford structurally and functionally diverse polyesters with controlled molecular weights and dispersities. However, the most common systems employ b

We report the synthesis and potential chirality of ortho-phenylenebisguanidines (BGs) with substituents at C(3) and C(6). Guanidinylation of 3,6-disubstituted benzene-1,2-diamines with 2-chloro-4,5-dihydro-1,3-dimethyl-1H-imidazolium chloride gave the corresponding BGs. X-Ray crystallography showed that the two guanidine moieties occupy different faces of the benzene ring, creating potential chirality, although optical resolution of tBu-substituted BG by chiral HPLC failed. However, a methylated acyclic bisguanidinium salt (BGms) was obtained as a chiral crystal with a space group of P212121.

A novel efficient asymmetric hydrogenation (AH) process was developed for the preparation of (R)-1-(3,5-bis(trifluoromethyl)phenyl)ethanol (3), using a catalyst Ru/(4R,5R)-(+)-4,5-bis(diphenylphosphinomethyl)-2,2-dimethyl-1,3-dioxoane-(R,R-Diop)-2R-(α-met

The present invention relates to a compound of formula I: or a pharmaceutically acceptable salt thereof, wherein the symbols are as defined in the specification; a pharmaceutical composition comprising the same, a method for treating or preventing a viral infection such as HIV using the same.

As catalysts for producing aromatic amines by hydrogenating aromatic nitrites, there are disclosed (1) the catalyst comprising a metal catalyst component comprising Ni and/or Co and a specific amount of zirconia as a carrier component, which is prepared b

PCT No. PCT/JP98/00464 Sec. 371 Date Sep. 30, 1998 Sec. 102(e) Date Sep. 30, 1998 PCT Filed Feb. 4, 1998 PCT Pub. No. WO98/33767 PCT Pub. Date Aug. 6, 1998The object of the invention is to provide a process for preparing a cyano group-containing methylamine, comprising hydrogenating only one of the two nitrile groups of a aromatic dinitrile, wherein the aromatic dinitrile is reacted a a high conversion ratio using a small amount of a catalyst under the conditions of a low temperature and a low pressure to prepare a cyano group-containing aromatic methylamine in a high yield.

The photocyclisation of 4>paracyclophanes with one or two unsaturated bridges, compounds 7 and 3, gives 3>(3,6)phenanthrenodiparacyclophane, 8, and 2>(2,13)pentahelicenoparacyclophane, 4, respectively.In contrast, 2

The invention provides organosilicon compounds of the formula: STR1 in which: N IS 1, 2 OR 3; Each R, which may be identical or different, is a monovalent organic group which contains a carbon-carbon double bond and from 2 to 10 carbon atoms; Each R1, which may be identical or different, is a straight or branched alkyl radical optionally substituted by one or more halogen atoms or cyano groups; an aryl radical or an alkylaryl radical optionally substituted by one or more halogen atoms; R2 is a straight or branched divalent alkylene or alkylidene radical possessing up to 4 carbon atoms; X is a divalent radical consisting of, or containing, at least one hetero-atom selected from oxygen, sulphur and nitrogen atoms, the radical being attached to the radical R2 via a said hetero-atom; G is an organic radical of valency (m+ l) possess from 1 to 30 carbon atoms; m is 1, 2 or 3; And each Y, which may be identical or different, is a functional group selected from: --NO2, STR2 --COOM (where M represents a sodium, potassium or lithium atom); --COOR4 ; STR3 --COCl; --OH; --OR4 ; STR4 --SH; --SR4 ; STR5 --CONH2 ; --CSNH2 ; --CN; --CH2 --NH2 ; --CHO; STR6 --NCO; STR7 wherein R3 represents a hydrogen atom or a straight or branched alkyl radical possessing up to 6 carbon atoms and R4 represents an alkyl radical possessing up to 4 carbon atoms, with the proviso that two Y groups can together constitute an imide group STR8 wherein R5 represents a hydrogen atom or a straight or branched alkyl radical possessing up to 4 carbon atoms. These are useful intermediates in the preparation of disilanes and silicon polymers, in particular of polyethylenic silicon compounds which can be polymerized with an α, ω-dihydrogenopolysiloxane to give thermoplastic elastomers.