Platelet protective efficacy of 3,4,5 trisubstituted isoxazole analogue by inhibiting ROS-mediated apoptosis and platelet aggregation

Thrombocytopenia is a major hematological concern in oxidative stress-associated pathologies and chronic clinical disorders, where premature platelet destruction severely affects the normal functioning of thrombosis and hemostasis. In addition, frequent exposure of platelets to chemical entities and therapeutic drugs immensely contributes in the development of thrombocytopenia leading to huge platelet loss, which might be fatal sometimes. Till date, there are only few platelet protective molecules known to combat thrombocytopenia. Hence, small molecule therapeutics are extremely in need to relieve the burden on limited treatment strategies of thrombocytopenia. In this study, we have synthesized a series of novel 3,4,5 trisubstituted isoxazole derivatives, among which compound 4a [4-methoxy-N'-(5-methyl-3-phenylisoxazole-4-carbonyl) benzenesulfonohydrazide] was found to significantly ameliorate the oxidative stress-induced platelet apoptosis by restoring various apoptotic markers such as ROS content, cytosolic Ca(2+) levels, eIF2-α phosphorylation, mitochondrial membrane depolarization, cytochrome c release, caspase activation, PS externalization, and cytotoxicity markers. Additionally, compound 4a dose dependently inhibits collagen-induced platelet aggregation. Hence, compound 4a can be considered as a prospective molecule in the treatment regime of platelet activation and apoptosis and other clinical conditions of thrombocytopenia. Further studies might ensure the use of compound 4a as a supplementary therapeutic agent to treat, thrombosis and CVD-associated complications. Over all, the study reveals a platelet protective efficacy of novel isoxazole derivative 4a with a potential to combat oxidative stress-induced platelet apoptosis

Support vector learning for gender classification using audio and visual cues

The paper investigated gender classification using Support Vector Machines (SVMs). The visual (thumbnail frontal face) and the audio (features from speech data) cues were considered for designing the classifier. Three different representations of the data, namely, raw data, principal component analysis (PCA) and non-negative matrix factorization (NMF) were used for the experimentation with visual signal. For speech, mel-cepstral coefficient and pitch were used for the experimentation. It was found that the best overall classification rates obtained using SVM for the visual and speech data were 95.31% and 100%, respectively, on data set collected in laboratory environment

A sequential one-pot tandem approach for the synthesis of 4-tosyl-5-aryloxazoles from carboxylic acids

An efficient method for the synthesis of 4-tosyl-5-aryloxazoles directly from aromatic carboxylic acids has been reported. The method involves the conversion of aromatic carboxylic acids to tosyl carboxylates by treating with tosyl chloride in the presence of potassium carbonate and its subsequent reaction with tosylmethyl isocyanide in the presence of sodium hydride to get 4-tosyl-5-aryloxazoles

Catalyst free sequential one-pot reaction for the synthesis of 3-indole propanoates/propanoic acid/propanamides as antituberculosis agents

A highly efficient catalyst free one pot four component synthesis of highly functionalized three-substituted indole derivatives has been reported. Thus, sequential catalyst free condensation of readily available aldehydes with Meldrum's acid followed by Michael addition of indole resulting three carbon component condensed product and concurrent decarboxylation by the nucleophilic attack of ethanol/water/amines affords three-indole propanoates/propanoic acid/propanamides in affordable yields. Further, synthesized compounds and standard drugs were evaluated against Mycobacterium tuberculosis H37Rv strain by Alamar blue assay method. Majority of the compounds exhibited the superior activity and specifically compound 4d has MIC 1.6 mu g/ml, which is better than the reference drugs used

Cyclization of Active Methylene Isocyanides with alpha-Oxodithioesters Induced by Base: An Expedient Synthesis of 4-Methylthio/Ethoxycarbonyl-5-acylthiazoles

Cyclization of tosylmethyl isocyanide with alpha-oxodithioesters in the presence of KOH is reported for the synthesis of 4-methylthio-5-acylthiazoles. Similarly, ethyl isocyanoacetate underwent cyclization with alpha-oxodithioesters to form 4-ethoxycarbonyl-5-acylthiazoles in the presence of DBU/EtOH. Mechanisms for the formation of thiazoles are proposed. These thiazoles can also be obtained by Takeda reaction, in which thiazole-4,5-anhydride is acylated with aromatic compounds followed by esterification; however, that approach requires two steps and suffers from the formation of a regioisomeric mixture of products

Base Induced Condensation of Malononitrile with Erlenmeyer Azlactones: An Unexpected Synthesis of Multi-Substituted Delta(2)-Pyrrolines and Their Cytotoxicity

An efficient, metal free approach to synthesize multi-substituted Delta(2)-pyrroline derivatives by mild base catalyzed cyclocondensation of malononitrile with Erlenmeyer azlactones via 1,2 addition was developed. The modularity of this reaction was used to assemble a range of poly-substituted pyrrolines. Further, synthesized products were screened for cytotoxic properties on different cancer cell lines such as A549 (Human lung adenocarcinoma cells), HeLa (Human cervical adenocarcinoma cells), Jurkat (Human chronic myeloid leukemia cells) and K562 (Human leukemic T cell Lymphoblast cells). Among the synthesized library of compounds, 6f and 6q displayed potent cytotoxic activity

The reaction of arylmethyl isocyanides and arylmethylamines with xanthate esters: a facile and unexpected synthesis of carbamothioates

An unexpected formation of carbamothioates by a sodium hydride-mediated reaction of arylmethyl isocyanides with xanthate esters in DMF is reported. The products thus obtained were compared with the carbamothioates obtained by the sodium hydride-mediated condensation of the corresponding benzylamines and xanthate esters in DMF. To account for these unexpected reactions, a mechanism is proposed in which the key steps are supported by quantum chemical calculations