A chemoenzymatic approach was developed to prepare sucrose-containing aromatic polymers. The protease from Bacillus licheniformis catalyzed the transesterification of sucrose with a diester of terephthalic acid in pyridine to give the mono- and diester products. At 45 degrees C, >70% of sucrose was consumed after 1 day and sucrose diester began to form after 6 days when >95% of sucrose had been...

A small satellite RNA of tobacco ringspot virus replicates in tissues infected with tobacco ringspot virus and accumulates in virus capsids, forming virus-like particles. Previous research showed that multimeric forms of this satellite RNA have tandem repeats of the "monomeric" satellite RNA sequence of 359 or 360 nucleotide residues. The multimeric RNAs undergo autolytic processing at a specif...

Thymidine 5´-bis[3-acetyloxy-2-cyano-2-(2-phenylethylcarbamoyl)propyl]phosphate (1) has been prepared and the removal of phosphate protecting groups by hog liver carboxyesterase (HLE) at pH 7.5 and 37 °C has been followed by HPLC. The first detectable intermediates are the (R(P))- and (S(P))-diastereomers of the monodeacetylated triester 14, which subsequently undergo concurrent retro-aldol con...

New macrocyclic polyether-diester ligands (3-5) containing the 4H-pyran-4-one subcyclic unit have been prepared by treating various glycols with dimethyl chelidonate (10). In the reaction of compound 10 with ethylene glycol and diethylene glycol, two noncyclic diester and tetraester (6-9) were produced in each case. The new marcocyclic ligand 4 formed stable complexes with benzylammonium pe...

The digestion in vitro by pancreatic lipase (EC 3.1.1.3) of the mono- and dioleate esters of hexane-1,6-diol has been studied. Under the conditions employed, the pathways for the lysis of these materials are proposed to be a hydrolysis step diester --> monoester + free fatty acid and a transesterification step 2 monoesters --> diester + free alcohol. If only the diester is present initially, it...

The deoxyoligonucleotide 5' AATCGGGCATGGATT (15-mer) was synthesized containing 12 phosphoramidate linkages derived from 2 primary and 2 secondary amines. The oligonucleotides were purified by reverse phase HPLC and characterized by PAGE. The thermal stability of the duplexes derived from these compounds, when hybridized to the complementary diester linked oligomer, were determined and compared...

The natural compounds of boron have many applications, primarily as a dietary supplement. research is based on the discovery that diester chlorogenoborate complex can be detected and quantified from green coffee beans. study reports such molecule also synthesized in stable form via direct reaction boric acid chlorogenic mixture acetonitrile–water (1:1, v/v) left to evaporate over period 48 h at...

Analogs of alternating purine-pyrimidine DNA polymers such as poly(dA-dT)-poly(dA-dT) can be made with phosphorothioate groups in the DNA backbone. A phosphorothioate diester at the 5'-purine-pyrimidine-3' step causes a significant lowering of the polymer's melting temperature compared to a phosphorothioate diester at the 5'-pyrimidine-purine-3' step. This may occur because sulfur substitution ...

new macrocyclic polyether-diester ligands (3-5) containing the 4h-pyran-4-one subcyclic unit have been prepared by treating various glycols with dimethyl chelidonate (10). in the reaction of compound 10 with ethylene glycol and diethylene glycol, two noncyclic diester and tetraester (6-9) were produced in each case. the new marcocyclic ligand 4 formed stable complexes with benzylammonium perchl...

The transferrin receptor is a target protein for phosphorylation by activated intracellular protein kinase C (May, W. S., Sahyoun, N., Jacobs, S., Wolf, M., and Cuatrecasas, P. (1985) J. Biol. Chem. 260, 9419-9426). Recently we reported that the potent tumor-promoting agent phorbol diester or a synthetic diacylglycerol could mediate rapid down-regulation of the surface transferrin receptor in a...