An efficient synthesis of tert-butyl-(2S)-2-[(tert-butoxycarbonyl)amino]-4-(2-oxiranyl) butanoate (5), the key intermediate for preparation of collagen cross-links (+)-pyridinoline (Pyd, 1) and (+)-deoxypyridinoline (Dpd, 2) was described from (4S)-5-(tert-butoxy)-4-[(tert-butoxycarbonyl)amino]-...

Continuous photo flow synthesis of tert-butyl 3-oxo-2-oxabicyclo[2.2.0]hex-5-ene-6-carboxylate (2b) from tert-butyl 2-oxo-2H-pyran-5-carboxylate (1b) has been investigated for scale-up synthesis of cis-3-(tert-butoxycarbonyl)-2,3,4-d3-cyclobutanecarboxylic acid (3c) as a useful building block fo...

The use of 1-tert-butoxy-2-tert-butoxycarbonyl-1,2-dihydroisoquinoline (BBDI) as a tert-butoxycarbonylation reagent for acidic proton-containing substrates such as phenols, aromatic and aliphatic amines hydrochlorides, and aromatic carboxylic acids in the absence of a base is described. The reac...

Conversion of (5S)-N-(tert-butoxycarbonyl)-5-(methoxycarbonyl)-2-pyrroline to its corresponding amide, an important intermediate in the synthesis of the dipeptidyl peptidase IV (DPP4) inhibitor Saxagliptin, was carried out by ammonolysis reaction catalyzed by immobilized Candida antarctica lipas...

The IR spectra of N-tert-butoxycarbonyl-amino acids and of the complex between N-tert-butoxycarbonyl-L-phenylalanine and pyridine are investigated at temperatures ranging from 25 to −180°C. A decrease of the temperature results in a contraction of the NH⋯O or OH⋯O hydrogen bonds. In this temper...

The fundamental possibility of acylative kinetic resolution of racemic heterocyclic amines was demonstrated by the example of all-cis-5-(4-bromophenyl)-4-tert-butoxycarbonyl-2-methoxycarbonylpyrrolidine. Individual enantiomers (ee >99%) were obtained in high yields via preparative chiral HPLC.

Novel acyl anion equivalents, lithiated diethyl 1-trimethylsilyloxy-alkylphosphonates, were successfully alkylated and converted to the corresponding ketones. The mechanism of the alkylation is discussed in connection with the Brook-Wittig rearrangement.

The rings considered in this article are commutative with identity. Modules are assumed to be unitary. Let R be a ring and let S be a multiplicatively closed subset of R. We say that a module M over R satisfiesS- strongaccr∗ if for every submodule N of M and for every sequence of elements of R,...

The calcium-sensing receptor antagonist (CaSR) has been recognized as a promising target of anabolic agents for treating osteoporosis. In the course of developing a new drug candidate for osteoporosis, we found tetrahydropyrazolopyrimidine derivative 1 to be an orally active CaSR antagonist that...

The reactions of (E)-1,2-difluoro-1,2-di (p-tolyl) ethene (1) with N-bromo- or N-chlorosuccinimide gave mainly the expected halofluorination products 1-bromo-1,2-di(p-tolyl)-1,2,2-trifluoroethane (2) or 1-chloro-1,2-di(p-tolyl)-1,2,2-trifluoroethane (4), respectively. As a side reaction halogena...

As a relatively new extractant, di-(2,3-dimethylbutyl)-phosphinic acid (HYY-2) is more efficient to separate heavy rare earths Tm/Yb/Lu than Cyanex 272 and P507. In this paper, HYY-2 was synthesized in our lab, and the extraction equilibrium, thermodynamics and stripping acidity for La, Gd and Y...

A comparative analysis was performed concerning the removal of two different organic dyes from model aqueous solution using an inorganic oxide adsorbent. The key element of the study concerns evaluation of the influence of the dyes’ structure and their acid-base character on the efficiency of t...

A systematic study of the synthesis of C.I. Acid Blue 9 leuco compound in water is reported. The kinetic analysis of experimental data for the condensation reaction between 2-formylbenzenesulfonic acid sodium and N-ethyl-N-(3′-sulfonic acid benzyl) aniline obtained at four different temperature...

2-(2H-Benzotriazol-2-yl)-4,6-di-tert-pentylphenol (UV 328, CAS: 25973-55-1) is an ultraviolet light (UV) absorber which is used as an additive for plastics and other polymeric substances to prevent the host material from light induced degradation reactions. However, no information about human ex...

A novel flow-injection spectrophotometry has been developed for the determination of molybdenum(VI) at nanograms per milliliter levels. The method is based on the catalytic effect of molybdenum(VI) on the bromate oxidative coupling of p-hydrazinobenzenesulfonic acid with N-(1-naphthyl)ethylenedi...

Two N-benzyl imines are designed to allow for carbon–carbon bond formations at the aminated benzylic positions. Direct benzylic arylation reactions of N-benzylxanthone imine with aryl chlorides proceed under palladium catalysis in the presence of cesium hydroxide, yielding the corresponding ben...

The involvement of nitric oxide (as sodium nitroprusside, SNP) in the reversal of glucose (Glu)-inhibited photosynthetic characteristics in the presence or absence of salt stress (100 mM NaCl) was studied in wheat (Triticum aestivum L.). The plants treated with either NaCl or 6% Glu exhibited re...

Sauerkraut is one of the most popular traditional fermented foods in northeastern China. The traditional northeast sauerkraut is mainly based on natural fermentation at a certain salt concentration. Salt concentration has important effects on the microbial structure, the dynamic changes of metab...

Erythrocyte acetylcholinesterase (AChE) is a preferred biomarker for the detection of organophosphorus poisoning. Acetylthiocholine (ATCh) is the most popular substrate for the detection of AChE activity. However, oximolysis is a prominent feature with ATCh. In this context, we have searched alt...

Upon treatment with the metal enolates of methylene active compounds (dimethyl malonate and dibenzoylmethane) (C-nucleophiles) and benzyl carbamate (N-nucleophile), d-allal- and d-galactal-derived vinyl epoxides are stereoselectively transformed, in a single step, into diastereoisomeric, highly ...