A procedure-dependent selective construction of two isomers of trimeric boronic esters was realized. A capsule-like trimeric boronic ester was constructed by the direct connection of two kinds of self-assembled boronic esters via [3+2] cycloaddition, while the tricyclic trimeric boronic ester was obtained by the self-assembly of pre-connected components.

Background To evaluate the possible association between phthalate esters (PEs) and the occurrence of endometriosis. Blood samples were collected from 99 infertile women with endometriosis (study group); 135 age-matched women without endometriosis (control group) but with infertility related to tubal defects, fibroids, polycystic ovaries, idiopathic infertility and pelvic inflammatory diseases d...

A series of acid-labile, optically pure ε-substituted δ-ketal-β-hydroxy esters were obtained by a Ru-SunPhos catalyzed asymmetric hydrogenation of the corresponding ε-substituted δ-ketal-β-keto esters. CaCO(3) played a dual role in the hydrogenation reaction--removing the acid generated during the formation of the catalyst and maintaining the activity of the catalyst.

The treatment of readily available propargylic indole-3-acetates with a catalytic amount of AuCl(PPh3)/AgSbF6 leads to tandem activations of the propargylic esters and the in situ generated allenylic esters, resulting in expeditious access to highly functionalized cyclobutanes with fused 2,3-indoline and gamma-lactone rings and an exocyclic E-double bond through sequential 3,3-rearrangement and...

les composes organophosphores en general et les esters phosphoriques en particulier, suscitent un interet, sans cesse grandissant , qui peut se justifier par l'importance de ces produits (nucleotides, phospholipides, etc.) dans les processus biologique. dans ce mernoire nous presentons les etudes des polyesters phosphoriques surtout sur le plan purement chimique. apres avoir mentionne les ...

in this research, (carboxy-3-oxopropylamino)-3-propylsilylcellulose (copapsc) as an organocatalyst, has been synthesized by grafting of succinic anhydride on the nh2-modified cellulose (cellulose functionalized with 3- aminopropyltriethoxysilane). the –co2h group-functionalized cellulose (copapsc) is used as a catalyst for the synthesis of coumarin derivatives from the reaction of phenolic subs...

The composition of liver cholesterol esters is the net resultant of several metabolic processes, including the uptake of chylomicron cholesterol esters originating in the intestinal tract (l), hydrolysis (2) and synthesis of cholesterol esters in the liver, and transport from the liver of cholesterol esters incorporated into plasma lipoproteins (3). Recent studies in viva have shown substantial...

Labile phosphate esters such as phosphocreatine, acetyl phosphate, and ribose-l-phosphate (1) have assumed great biological importance. These esters are so unstable that they are split with great rapidity by the reagents commonly used for inorganic phosphate determination. Therefore, the usual inorganic phosphate measurements in tissue extracts, etc., actually represent the sum of the inorganic...

background: to evaluate the possible association between phthalate esters (pes) and the occurrence of endometriosis. blood samples were collected from 99 infertile women with endometriosis (study group); 135 age-matched women without endometriosis (control group) but with infertility related to tubal defects, fibroids, polycystic ovaries, idiopathic infertility and pelvic inflammatory diseases ...

Procedures for preparing 4,4-dimethyloxazoline (DMOX) and pyrrolidine derivatives from fatty acid methyl esters (FAMEs) were modified to provide milder simpler conditions the derivatization reactions widely used in mass spectrometric analysis of acids. DMOX obtained overnight at room temperature presence sodium borohydride. The proposed method, involving a low-temperature condensation-cyclizati...