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In this study, we synthesized a new thiosemicarbazone derivative molecule (5) that exhibits sensor properties. The characterization of the synthesized molecule was performed using spectroscopic methods such as 1H−, 13C–NMR, FT–IR and Q–TOF. PVC‐membrane ion‐selective sensors were prepared in which the synthesized molecule was used as an ionophore. Surface images of the prepared sensors were examined by scanning electron microscope (SEM) technique. The prepared sensors exhibited selectivity towards barium(II) ions. The developed barium(II)‐selective sensor had a low detection limit of 5.54×10−7 M in the concentration range of 1.0×10−1–1.0×10−6 M. The proposed barium(II)‐selective sensor had fast response time, good repeatability and stability, and can be manufactured with low cost. The sensor can detect barium(II) ions in various water samples with very high recoveries. [ABSTRACT FROM AUTHOR]

The secondary sulfonamide derivatives containing benzothiazole scaffold (1–10) were synthesized to determine their inhibition properties on two physiologically essential human carbonic anhydrases isoforms (hCAs, EC, 4.2.1.1), hCA I, and hCA II. The inhibitory effects of the compounds on hCA I and hCA II isoenzymes were investigated by comparing their IC50 and Ki values. The Ki values of compounds (1–10) against hCA I and hCA II are in the range of 0.052 ± 0.022–0.971 ± 0.280 and 0.025 ± 0.010–0.682 ± 0.335, respectively. Some of these inhibited the enzyme more effectively than the standard drug, acetazolamide. In particular, compounds 5 and 4 were found to be most effective on hCA I and hCA II. [ABSTRACT FROM AUTHOR]

Enantiopure benzo-fused cyclic alcohols have been used as a building block of a drug for Parkinson's disease. Biocatalytic reduction of ketones is one of the most promising and significant routes to prepare optically active alcohols. In this study, the reductive capacity of seven lactic acid bacteria (LAB) strains were investigated as whole-cell biocatalyst in the enantioselective reduction of 1-indanone (1). Lactobacillus paracasei BD71 was found to have the best reductive capacity. Effects of different parameters such as pH, incubation time, agitation speed and temperature, on enantiomeric excess (ee) and conversion were investigated in a bioconversion. (S)-1-indanol ((S)-2) could be used as precursor for the synthesis of rasagiline mesylate TVP1012 for the therapy of Parkinson's illness. It was produced in gram-scale (5.24 g), high yield (93%) and enantiomerically pure form using L. paracasei BD71 whole-cell biocatalysts. Also, to our knowledge, this is the first report on production of (S)-2 using whole-cell catalyst in enantiopure form, excellent yield, conversion and gram scale. This is a cheap, clean and eco-friendly process for production of (S)-2 compared to chemical processes. [ABSTRACT FROM AUTHOR]

A series of novel sulfonates containing quinazolin‐4(3H)‐one ring derivatives was designed to inhibit aldose reductase (ALR2, EC 1.1.1.21). Novel quinazolinone derivatives (1–21) were synthesized from the reaction of sulfonated aldehydes with 3‐amino‐2‐alkylquinazolin‐4(3H)‐ones in glacial acetic acid with good yields (85%–94%). The structures of the novel molecules were characterized using IR, 1H‐NMR, 13C‐NMR, and HRMS. All the novel quinazolinones (1–21) demonstrated nanomolar levels of inhibitory activity against ALR2 (KIs are in the range of 101.50–2066.00 nM). Besides, 4‐[(2‐isopropyl‐4‐oxoquinazolin‐3[4H]‐ylimino)methyl]phenyl benzenesulfonate (15) showed higher inhibitor activity inhibited ALR2 up to 7.7‐fold compared to epalrestat, a standard inhibitor. Binding interactions between ALR2 and quinazolinones have been investigated using Schrödinger Small‐Molecule Drug Discovery Suite 2021–1, reported possible inhibitor‐ALR2 interactions. Both in vitro and in silico study results suggest that these quinazolin‐4(3H)‐one ring derivatives (1–21) require further molecular modification to improve their drug nominee potency as an ALR2 inhibitor. [ABSTRACT FROM AUTHOR]

Biocatalytic asymmetric reduction of ketone is an efficient method for the production of chiral carbinols. The study indicates selective bioreduction of different ketones (1–8) to their respective (R)-alcohols (1a–8a) in low to high selectivity (0- >99%) with good yields (11–96%). In this work, whole-cell of Lactobacillus kefiri P2 catalysed enantioselective reduction of various prochiral ketones was investigated. (R)-4-Phenyl-2-butanol 2a, which is used as a precursor to antihypertensive agents and spasmolytics (anti-epileptic agents), was obtained using L kefiri P2 in 99% conversion and 91% enantiomeric excess (ee). Moreover, bioreduction of 2-methyl-1-phenylpropan-1-one substrate 8, containing a branched alkyl chain and difficult to asymmetric reduction with chemical catalysts as an enantioselective, to (R)-2-methyl-1-phenylpropan-1-ol (8a) in enantiomerically pure form was carried out in excellent yield (96%). The gram-scale production was carried out, and 9.70 g of (R)-2-methyl-1-phenylpropan-1-ol (8a) in enantiomerically pure form was obtained in 96% yield. Also especially, the yield and gram scale of (R)-2-methyl-1-phenylpropan-1-ol (8a) synthesised through catalytic asymmetric reduction using the biocatalyst was the highest report so far. The efficiency of L kefiri P2 for the conversion of the substrates and ee of products were markedly influenced by the steric factors of the substrates. This is a cheap, clean and eco-friendly process for production of chiral carbinols compared to chemical processes. [ABSTRACT FROM AUTHOR]

Asymmetric bioreduction of ketones is a fundamental process in the production of organic molecules. Compounds containing tetralone rings are found in the structure of many biologically active and pharmaceutical molecules. Biocatalytic reduction of ketones is one of the most promising and significant routes to prepare optically active alcohols. In this study, the reductive capacity of Lactobacillus paracasei BD101 was investigated as whole‐cell biocatalyst in the enantioselective reduction of 1‐tetralone (1). In biocatalytic reduction reactions, the conversion of the substrate and the enantiomeric excess (ee) of the product are significantly affected by optimization parameters such as temperature, agitation rate, pH, and incubation time. Effects of these parameters on ee and conversion were investigated comprehensively. (R)‐1‐tetralol ((R)‐2), which can be used to treat disorder such as obsessive compulsive, post‐traumatic stress, premenstrual dysphoric, and social anxiety, was manufactured in enantiopure form, high yield and gram‐scale, using whole‐cell biocatalysts of L. paracasei BD101. The 7.04 g of (R)‐2 was obtained in optically pure form with 95% yield. Also, to our knowledge, this is the first report on production of (R)‐2 using whole‐cell biocatalyst in excellent yield, conversion, enantiopure form and gram scale. This is a clean, eco‐friendly and cheap method for the synthesis of (R)‐2 compared with chemical catalyst. [ABSTRACT FROM AUTHOR]

A novel method for the production of singlet oxygen from H2O2 was developed. A combination of iodoarene (ArI), methyltrioxorhenium (MTO), and H2O2 in the presence of pyridine as the co-catalyst efficiently produced singlet molecular oxygen (1O2) under biphasic conditions. The existence of 1O2 was demonstrated by trapping experiments with aromatic dienes, 1,3-cyclodienes, and alkenes. The mechanism of 1O2 production from the iodoarene/MTO/35 % H2O2 system and the reaction scope was also discussed. [ABSTRACT FROM AUTHOR]

Mast cells have been linked to rheumatoid arthritis (RA) and are essential to the pathogenesis of RA-like disease in a mouse model. We describe a 34-year-old woman who developed Sjögren's syndrome concurrently with telangiectasia macularis eruptiva perstans (TMEP), a rare form of cutaneous mastocytosis. The patient had sicca symptoms with an abnormal minor salivary gland biopsy and decreased salivary flow, peripheral neuropathy, an 80 pound weight loss, and a macular erythematous rash that exhibited superficial perivascular mast cell infiltrates on biopsy of lesional skin. This case further underscores the link between mast cells and the development of autoimmunity.