Methyl 2-azido-3-O-benzyl-2-deoxy-α-D-mannofuranoside (4), readily available from D-glucose, is a common intermediate in the enantiospecific syntheses of deoxymannojirimycin [1,5-dideoxy-1,5-imino-D-mannitol](l), fagomine [1,2,5-trideoxy-1,5-imino-D- arabino hexitol] (2) and 2R,5R-dihydroxymeth...

Compared with those of p-terphenyl, the absorption and fluorescence spectra of its 1-nitro, 4″-amino derivative in dioxane exhibit additional long-wave bands. These are assigned to transitions involving a series of excited configurations, of increased electron delocalization and lower energy, p...

Organic dyes containing trifluoromethylated-pyrazolo[3, 4-b]quinoline were synthesized by using condensation reaction between substituted pyrazolo-4-formaldehyde and aryl amines in moderate yields. Quantum calculation, electrochemical, photophysical, and electroluminescent properties were discus...

Reaction of the Ruppert–Prakash reagent (Me3SiCF3) with aromatic aldehydes in the presence of triphenylphosphine, lithium iodide and lithium tetrafluoroborate selectively furnishes gem-difluorinated phosphonium salts. Simple alkaline hydrolysis of these salts results in difluoromethylated produ...

It was found that during the optical resolution of (N-alkyl)-pipecolic acid-anilides by 2R,3R- tartaric acid and O,O′-dibenzoyl-2R,3R-tartaric acid that the precipitated diastereoisomer was not the salt but a diastereoisomeric complex in 8 cases from 13. The results indicate that tartaric acids...

The synthesis and metallation of 4-methoxypicolin- and 2-methoxyisonicotin-anilides as a way of regiospecific transformation of picolinic and isonicotinic acids into 2, 3, 4-trisubstituted pyridines, is described. The resulted C3 - alkylated derivatives underwent smooth acid - catalysed conversi...

Isomerization of N-allylamides catalyzed by ruthenium and rhodium complexes to corresponding 1-propenyl derivatives is described. The first catalytic system containing a precursor ({[RuCl2(1,5-COD)]x}), tris(2,4-di-t-butylphenyl)phosphite and CaH2 for highly (Z)-selective isomerization of allyla...

We synthesized and evaluated a series of 5-(1-methyl-3-trifluoromethyl-1H-pyrazol-5-yl)-2-thiophenecarboxamides to identify potent inhibitors of calcium-release-activated calcium (CRAC) channels with greater selectivity than voltage-operated calcium (VOC) channels. These efforts resulted in iden...

A method for the quantitative determination of 4-hydroxy-3-methoxyphenyl glycol and its conjugates in human cerebrospinal fluid has been developed. Unconjugated 4-hydroxy-3-methoxyphenyl glycol and its conjugates after hydrolysis (81% efficiency) were reacted with trifluoroacetic anhydride. The ...

The Kabachnik–Fields reaction of 4-piperidone hydrochloride monohydrate, an aromatic aldehyde and triethyl phosphite in the presence of triethylamine and magnesium perchlorate affords diethyl (aryl)(4-oxopiperidin-1-yl)methylphosphonates in moderate yields.

4-[(2RS,3RS)-3-Hydroxy- (1b) and -3-(4-chlorophenoxy)-1-(4-methoxyphenyl)-4-oxoazetidin-2-yl]thiazol-2(3H)-one (16b) were synthesised. While the former was smoothly rearranged into (5RS)-5-hydroxy-7-(4-methoxyphenyl)-1,5-dihydrothiazolo[3,4-a]pyrazine-3,6(7H)-dione (7b) on treatment with Na2CO3 ...

A new optical sensor for sensing of Pb2+ in immobilized medium (PVC film) and ethanol medium was developed by using 5,10,15,20-tetra-(3-bromo-4-hydroxyphenyl)porphyrin (TBHPP) synthesized. The sensor-based TBHPP showed a linear response towards Pb2+ in concentration range from 5 × 10−6 to 4 × ...

Starting from 4-chloropyridine and 2,6-dialkylphenoxides, 4-(3,5-dialkyl-4-hydroxyphenyl)pyridines are obtained via an electrochemically induced SRN1 reaction using 2,4′ -bipyridine as a mediator (alkyl= pentyl, isopropyl, methyl). Quaternization of 4-(3,5-dipentyl-4-hydroxyphenyl)pyridine by l...

Different nonionic surfactants derived from hydroxyphenyl propionic acid have been synthesized (HTOPD, HTOPT and HTOPH) and their vital role in the preparation process of silver nanoparticles has been assured, using transmission electron microscope, UV–Vis Spectroscopy and dynamic light scatter...

Three monomers were prepared from 4,4-bis(4′-hydroxyphenyl)valeric acid (BHVA) namely its methylester (BHVAM), its bis-acetylated methylester (BAVAM) and its 4,4-bis(4′-acetoxyphenyl)valeric acid (BAVA). All three monomers were polycondensed in bulk at various temperature profiles using Ti(OBu...

To stabilize an iron(III)-porphyrin catalyst in the presence of peroxide such as KHSO5, 5,10,15,20-tetrakis(4-hydroxyphenyl)-porphine iron(III) (FeTPP(OH)4) was introduced into a humic acid (HA) via formaldehyde polycondensation to produce a “resol” catalyst. FeTPP(OH)4 can have four phenolic ...

As operation performance of electro-oxidation is strongly influenced by feature of anode materials, apparently oriented preparation of electrode materials to maximize stable degradation efficiency would be top-priority consideration for system optimization. Recently, heteroatoms hybrid graphene ...

Time-resolved resonance Raman spectra are obtained for the lowest excited triplet state T1 and the radical cation of 5-dibenzosuberenol (DBCH-5-ol). It is concluded, based on the large downshifts of the Raman bands assignable to the CC stretch of the central ring, that the CC bond is weakene...

Hydrogels have been proposed as candidates for tissue replacement; however, current systems are often highly susceptible to hydrolytic degradation and have not been shown to mimic the viscoelastic behavior of the native tissue when subjected to dynamic loading conditions. In the present work, 1,...

The synergesic effect from copolymerising polysiloxane and epoxy functionality offer a viable encapsulant material for use in electronic devices. A series of epoxy group-containing organopolysiloxane without ether bond spacer was prepared. The cross-link density was progressively monitored by co...