deprotection of phosphate, phosphate, and sulfite esters by silica chloride is described. silica chloride is a mild, selective, and effective reagent for cleavage of benzyl and t-butyl esters of the above compounds.

A general, mild and efficient protocol has been developed for the synthesis of esters and thioesters. The process has been taking place using tetra n-butylammonium iodide (TBAI) as a phase-transfer catalyst and in the presence of potassium carbonate (K2CO3). A wide range of esters and thioesters was prepared in high yields and suitable times by the treatment of alcohols, phenols and thiols with...

Gas-tight dense membranes of highly Sr-doped LaCoO, (such as the composition La,,, Sr 0,7 COO, chosen in this study) are difficult to prepare using usual synthesis processes. This report presents an aqueous sol-gel route using metal acetates as precursors to achieve this goal. Hydrogen peroxide and ammonia are added to the acetates precursor solution to obtain stable sol and xerogel, as well as...

 Caffeic acid phenethyl ester(CAPE) suppresses the growth of transformed cells such as human breast cancer cells, hepatocarcinoma , myeloid leukemia, colorectal cancer cells, fibrosarcoma, glioma and melanoma. A group of heterocyclic esters of caffeic acid was synthesized using Mitsunobu reaction and the esters were subjected to further structural modification by electrooxidation of the catecho...

A series of (R)-N-Cbz-2-alkyl-2-amino-3-hydroxypropyl acetates was prepared by enzymatic acetylation of NCbz-2-alkyl-2-aminopropane-1,3-diols with immobilized lipoprotein lipase from Pseudomonas sp. in up to 98% enantiomeric excess (ee). Enantiodivergent oxidation of (R)-N-Cbz-2-alkyl-2-amino-3-hydroxypropyl acetates readily furnished (R)and (S)-substituted serines ( -benzylserines and -methyls...

The short syntheses of each of the mono-acetates of N-acetyl-D-neuraminic acid are reported. These are important molecules for studying the mechanism and function of enzymes which utilise Neu5Ac as a substrate. However, until now these molecules were not available as pure compounds and instead had to be studied as mixtures. Neu4,5Ac(2) and Neu5,8Ac(2) were synthesised from a common precursor in...

a general, mild and efficient protocol has been developed for the synthesis of esters and thioesters. the process has been taking place using tetra n-butylammonium iodide (tbai) as a phase-transfer catalyst and in the presence of potassium carbonate (k2co3). a wide range of esters and thioesters was prepared in high yields and suitable times by the treatment of alcohols, phenols and thiols with...

conjugation of methotrexate (mtx) (mw 454) with different molecular weights of polyethylene glycol (peg) including methoxy-peg (mpeg) 750 d and 5000 d and diol-peg 35000 d led to compounds that are physicochemically highly different from the parent compound, mtx. in this study, an hplc system consisting of c8 column and uv detector (?=342 nm), using a mixture of 30:70 v/v phosphate-citrate buff...

A fast and efficient phenylselenylation of allyl acetates by diphenyl diselenide and indium(I) bromide has been achieved in neat under the catalysis of Ru(acac)(3). The intermediate complex of diphenyl diselenide and indium has been isolated and identified as a polymeric pentacoordinated In(III) selenolate complex, [In(SePh)(3)](n).

A copper-catalyzed asymmetric propargylic amination with a chiral ketimine P,N,N-ligand that proceeds via decarboxylation of propargyl carbamates has been developed. The reaction can be performed under the mild condition for a broad range of substrates, providing the corresponding propargylic amines in high yields and with up to 97% ee. This reaction represents a new and facile access to optica...