Phytochemical profiling, antioxidant and antiproliferation potential of Euphorbia milii var.: Experimental analysis and in-silico validation.

This study was aimed to investigate the anticancer potential of Euphorbia milii (E. milii) using an exquisite combination of phytopharmacological and advanced computational techniques. The chloroform fraction (Em-C) of E. milii methanol extract showed the highest antioxidant activity (IC50: 6.41 ± 0.99 µg/ml) among all studied fractions. Likewise, Em-C also showed significant cytotoxicity (IC50: 11.2 ± 0.8 µg/ml) when compared with that of standard compound 5-fluorouracil (5-FU) (IC50: 4.22 ± 0.6 µg/ml) against hepatocarcinoma cell line (HepG2). However, in a human cervical cancer cell line (HeLa), Em-C demonstrated a non-significant difference in cytotoxicity (22.1 ± 0.8 µg/ml) when compared with that of 5-FU (IC50: 6.87 ± 0.5 µg/ml). Furthermore, Western blot and qRT-PCR analysis revealed that the suppression of HepG2 cells was the consequence of a tremendous decrease in CDK2 and E2F1 protein expression. The GC-MS analysis of Em-C revealed the unique presence of cyclobarbital (CBT) and benzodioxole derivative (BAN) as major constituents. Furthermore, molecular docking of compounds BAN, CBT, and MBT into the binding site of different molecular targets i.e. cyclin dependent kinase 2 (CDK2), thymidylate synthase (TS), caspase 3, BCL2 and topoisomerase II was carried out. Compounds BAN and CBT have demonstrated remarkable binding affinity towards CDK2 and thymidylate synthase, respectively. Molecular dynamic simulation studies have further confirmed the finding of docking analysis, suggesting that CDK2 and TS can act as an attractive molecular target for BAN and CBT, respectively. It can be concluded that these E. milii phytoconstituents (BAN and CBT) may likely be responsible for anti-invasive activity against HepG2 cells.

Development of a rapid resolution HPLC method for the quantitative determination of sitagliptin in Human plasma.

A new high performance liquid chromatography (HPLC) method for the quantitative determination of sitagliptin in human plasma was developed and validated for pharmacokinetics study. The plasma was spiked with the internal standard (Salbutamol, IS), extracted with trichloro acetic acid. The extracted analyte was injected into a Symmetry® ODS C18 column (250mm×4.5mm, 5m) and the flourometric detector was operated at 267nm for excitation and 575nm for emission. The mobile phase consisting of Potassium dihydrogen phosphate buffer pH (4.9)-Acetonitrile-Methanol (30:50:20 v/v) at flow rate of 1.0mL/min. The method showed high specificity. Calibration curves of the peak area ratio of each analyte/IS versus sitagliptin concentration were linear in the range of 0.122-31.25µg/mL (r>0.989) for plasma and 0.012-25ug/ml for QC solution(r>0.995). The lower limit of quantification (LLOQ) was 0.122µg/mL in plasma and 0.012 in QC solution. The intraday and interday coefficient of variation was lower than 10%. The accuracy (relative recovery) at three levels was 100.95%, 101.03% and 97.79% respectively. The extraction recovery was 97.6%, 92.2% and 91.96% at the concentrations of 6.25, 25 and 100µg/mL, respectively. Short term and long term, freeze thaw stability of standard solutions and plasma samples were satisfactory. The optimized HPLC method was validated and proved to be specific, robust and accurate for determination of Sitagliptin in human plasma.

Antioxidant and lipoxygenase inhibiting new iridoid glucosides from Caryopteris odorata.

The phytochemical investigation of the ethylacetate-soluble fraction of Caryopteris odorata (Ham. ex Roxb.) led to the isolation of four new iridoid glucosides (1-4): 8-O-trans-cinnamoyl caryoptoside (1), 8-O-trans-cinnamoyl shanzhiside methylester (2), 8-O-trans-cinnamoyl mussaenoside (3) and 8-O-cafeoyl massenoside (4). The structures of these compounds were determined by FAB-MS, IR, 1D and 2D-NMR spectroscopy and by comparing with the published data of the closely related compounds. The antioxidant potential of the isolated iridoids (1-4) was evaluated relative to conventionally used standards and these molecules exhibited good antioxidant potential. Moreover, their inhibitory potential was also screened against three enzymes, namely acetyl cholinesterase, butyrylcholinesterase and lipoxygenase. These iridoid glucosides were found to be inactive against acetyl and butyrylcholinesterases but active against lipoxygenase.

2-Phenitidine derivatives as suitable inhibitors of butyrylcholinesterase

This manuscript reports the synthesis of a series of N-substituted derivatives of 2-phenitidine. First, the reaction of 2-phenitidine (1) with benzene sulfonyl chloride (2) yielded N-(2-ethoxyphenyl) benzenesulfonamide (3), which further on treatment with sodium hydride and alkyl halides (4a-g) furnished into new sulfonamides (5a-g). Second, the phenitidine reacted with benzoyl chloride (6) and acetyl chloride (8) to yield the reported N-benzoyl phenitidine (7) and N-acetyl phenitidine (9), respectively. These derivatives were characterized by infrared spectroscopy, ¹H-NMR, and EI-MS, and then screened against acetylcholinesterase, butylcholinesterase, and lipoxygenase enzyme, and were found to be potent inhibitors of butyrylcholinesterase alone.

Este trabalho apresenta a síntese de uma série de derivados da 2-fenetidina N-substituídos. Primeiro, a reação da 2-fenetidina (1) com cloreto de benzenossulfonila (2) conduziu à N-(2-etoxifenil)benzenossulfonamida (3) que, após tratamento com hidreto de sódio e haletos de alquila (4a-g), originou novas sulfonamidas (5a-g). Em segundo lugar, a reação da fenetidina com cloreto de benzoíla (6) e cloreto de acetila (8) conduziu, respectivamente, à N-benzoilfenetidina (7) e N-acetilfenetidina (9). A caracterização destes derivados fez-se por IV, ¹H-RMN e EM-IE. Procedeu-se à avaliação da atividade inibidora destes compostos em relação às enzimas acetilcolinesterase, butirilcolinesterase e lipoxigenase. No entanto, apenas revelaram atividade inibidora da butirilcolinesterase.

Synthesis, characterization and biological screening of sulfonamides derived form 2-phenylethylamine.

In the present study, a series of N-substituted derivatives of 2-phenylethylamine has been synthesized. The reaction of 2-phenylethylamine (1) with benzene sulfonyl chloride (2) yielded N-(2-phenylethyl) benzenesulfonamide (3), which further on treatment with alkyl/acyl halides (4a-i) in the presence of sodium hydride furnished into N-substituted sulfonamides (5a-i). These derivatives were characterized by IR, (1)H-NMR and EI-MS and then screened against acetyl cholinesterase (AChE), butyryl cholinesterase (BChE) and lipoxygenase enzyme (LOX) and were found to be potent inhibitors of butyryl cholinesterase only.

Lipoxygenase inhibitory sphingolipids from Launaea nudicaulis.

Four new sphingolipids: nudicaulin A [(2S,3S,4R,14E)-2-{[octadecanoyl]amino}tetraeicos-14-ene-1,3,4-triol; 1], nudicaulin B [(2S,3S,4R,14E)-2-{[(2R)-2-hydroxyoctadecanoyl]amino}tetraeicos-14-ene-1,3,4-triol; 2], nudicaulin C [(2S,3S,4R,14E)-2-{[(2R)-2-hydroxyoctadecanoyl]amino}tetraeicos-14-ene-1,3,4-triol-1-O-ß-D-glucopyranoside; 3], and nudicaulin D [(2S,3S,4R)-2-{[(2R,3S,12E)-2,3-dihydroxyeicos-12-enoyl]amino}octadecane-1,3,4-triol; 4] together with 1-hexatriacontanol, ß-sitosterol, octadecyl 4-hydroxycinnamate, elaidic acid, cholesta-5,22-diene-3,7-diol, oleanolic acid, apigenin, and ß-sitosterol 3-O-ß-D-glucopyranoside were isolated from the methanolic extract of the whole plant of Launaea nudicaulis. Their structures were elucidated using ¹H and ¹³C NMR spectra and 2D NMR analyses (HMQC, HMBC, and COSY) in combination with mass spectrometry (EI-MS, HR-EI-MS, FAB-MS, and HR-FAB-MS) experiments and comparison with literature data of related compounds. Compounds 1-4 displayed moderate inhibitory potential against enzyme lipoxygenase in concentration-dependent manner with IC50 value ranges 103-193 µM.

Synthesis of new sulfonamides as lipoxygenase inhibitors.

The present study describes a convenient method for the synthesis of new lipoxygenase inhibitors, 4-(toluene-4-sulfonylamino)-benzoic acids from p-amino benzoic acid. Reaction of p-amino benzoic acid with p-toluenesulfonyl chloride provided thirteen N- and O-alkylation products 4a-4m in moderate to good yields. Lipoxygenase inhibition of newly formed sulfonamide derivatives was investigated and some of these compounds 4m, 4g, 4e, 4f and 4j showed good lipoxygenase inhibitory activities with IC(50) values ranged between 15.8 ± 0.57 and 91.7 ± 0.61 µmol whilst all other compounds exhibited mild anti-lipoxygenase activities with IC(50) values ranged between 139.2 ± 0.75 and 232.1 ± 0.78 µmol. N-alkylated products were more active against the enzyme than O-alkylated or both N- and O-alkylated ones. All synthesized sulfonamides were recrystallized in chloroform to give these title compounds which were characterized using FTIR, (1)H NMR, (13)C NMR, elemental analysis and single crystal X-ray diffraction techniques.