Analysis of amide bond formation with an alpha-hydroxy-beta-amino acid derivative, 3-amino-2-hydroxy-4-phenylbutanoic acid, as an acyl component: byproduction of homobislactone.

In the synthesis of peptidomimetics containing alpha-hydroxy-beta-amino acid, the coupling of this N(beta)-protected beta-amino acid with amine components was generally performed without the protection of its alpha-hydroxyl group. However, the formation of dipeptides in low yield was often observed when sterically hindered amine components were used. Boc-Apns-OH [Apns: (2S,3S)-3-amino-2-hydroxy-4-phenylbutanoic acid, allophenylnorstatine] (6), which is one of such beta-amino acid derivatives, is intensively employed as a core structure in the development of HIV-1 protease inhibitors.

Determination of N-acetylneuraminic acid and N-glycolylneuraminic acid in glycoproteins by high-performance liquid chromatography without derivatization.

A simple and sensitive method for the determination of N-acetylneuraminic acid and N-glycolylneuraminic acid in glycoproteins by high-performance liquid chromatography has been investigated. The best condition to release sialic acid from glycoproteins involved incubation at 80 degrees C for 1 h in vacuo in 0.01 M hydrochloric acid with removal of the hydrochloric acid by evaporation without decomposing the sialic acids.

Vitronectin diversity in evolution but uniformity in ligand binding and size of the core polypeptide.

We isolated vitronectins from the plasma or sera of 14 animal species including mouse and rat by heparin affinity chromatography. They cross-reacted with anti-vitronectin antibody and their amino terminal sequences showed strong homology. They also promoted spreading of BHK cells and were bound to heparin and collagen in the same way.

Direct carbohydrate analysis of glycoproteins electroblotted onto polyvinylidene difluoride membrane from sodium dodecyl sulfate-polyacrylamide gel.

A procedure for the carbohydrate analysis of glycoproteins electrotransferred to a polyvinylidene difluoride membrane is described. The glycoproteins (plant lectins, transferrin, and vitronectin) were first separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and then electroblotted onto a membrane. Each of the glycoprotein bands visualized by staining with Coomassie brilliant blue R-250 was excised from the membrane and subjected to direct hydrolysis either in 2.