The adduct [MeO → Bpin-Bpin](-) efficiently mediates the β-boration of α,β-unsaturated imines formed in situ. The use of chiral phosphines as additives, and in particular the chiral phosphine (S)-MeBoPhoz, enables the catalytic asymmetric reaction to proceed with higher enantioselectivity than the analogue copper(I) mediated reaction.

The oxidation of Ni(II) N-confused porphyrins (NCPs) with azo radical initiators resulted in an unexpected intramolecular nucleophilic substitution reaction via a proposed Ni(III) NCP intermediate, which could be detected by HRMS.

The writers have been studying an antigen-antibody system in which the antigen was the red dye, R-salt-azo-benzidine-azo-crystalline egg albumin 1 (1, 2), fractionated to the extent that it reacted only exceptionally with anti-egg albumin sera. However, as stated previously (2), the original specificity was not entirely abolished, since antisera to the dye protein yielded precipitates with crys...

1. The inhibition of pepsin-catalysed hydrolysis of N-acetyl-l-phenylalanyl-l-phenylalanylglycine by products and product analogues was studied. 2. The non-competitive nature of the inhibition by the product N-acetyl-l-phenylalanine confirms an ordered release of products, and points to a common mechanism (involving an amino-enzyme) for pepsin-catalysed transpeptidation and hydrolysis reactions...

In the title compound, C(9)H(9)N(5)O(6), the azo group adopts a trans conformation and the dihedral angles between the two nitro groups and the benzene ring are 11.6 (3) and 21.3 (3)°.

A convenient and practical synthesis of imidazol-1-yl-acetic acid hydrochloride was achieved via N-alkylation of imidazole using tert-butyl chloroacetate followed by a non-aqueous ester cleavage of the resulting imidazol-1-yl-acetic acid tert-butyl ester in the presence of titanium tetrachloride. The synthesized imidazol-1-yl-acetic acid hydrochloride was then utilized to prepare zoledronic acid.

The title compound, (C(13)H(16)N(4))[ZnCl(4)], consists of a tetra-hedral [ZnCl(4)](2-) anion and a 2-{2-[4-(dimethyl-amino)-phen-yl]diazen-1-ium-1-yl}pyridinium dication. The pyridinium-N atom is syn to the azo bond which allows for the formation of an intramolecular N-H⋯N hydrogen bond. In the crystal, the cation and anion are held together by N-H⋯Cl hydrogen-bond inter-actions involving the ...

A serine proteinase (ycaB) from the yeast Candida albicans A.T.C.C. 10261 was purified to near homogeneity. The enzyme was almost indistinguishable from yeast proteinase B (EC 3.4.21.48), and an Mr of 30,000 for the proteinase was determined by SDS/polyacrylamide-gel electrophoresis. The initial site of hydrolysis of the oxidized B-chain of insulin, by the purified proteinase, was the Leu-Tyr p...

a convenient and efficient direct protocol for the preparation of antibacterial azo dyes by the reaction of 2-naphthol with aromatic amines in the presence of catalytic amount of n-methyl-2-pyrrolidonium hydrogen sulfate ([h-nmp]hso4) was carried out under solvent free conditions. this method has some advantages such as: easy work-up and easy separation of catalyst from the reaction mixture. th...

Pada proses pembuatan biodiesel terdapat tahapan yaitu tahap persiapan, transesterifikasi, pemisahan mestil ester, pencucian metil dan pemurnian ester. dilakukan pemanasan ester dengan tujuan untuk menghilangkan sisa metanol air yang masih terkandung dalam Oleh karena itu diperlukan desain evaporator sesuai mendapatkan kemurnian produk akan berpengaruh pada kinerja mesin digunakan jangka pendek...