Biochemical evaluation and ligand binding studies on glycerophosphodiester phosphodiesterase from Staphylococcus aureus using STD-NMR spectroscopy and molecular docking analysis.

Glycerophosphodiester phosphodiesterase (GDPD) is a highly conserved enzyme in both prokaryotic and eukaryotic organisms. It catalyses the hydrolysis of various glycerophosphodiesters into glycerol-3-phosphate and corresponding alcohols, which serve as building blocks in several biosynthetic pathways. This enzyme is a well-known virulence factor in many pathogenic bacteria, including Staphylococcus aureus, and is thus considered a potential drug target. In this study, competent E. coli BL21(DE3)pLysS expression cells were used to express the GDPD enzyme from vancomycin-resistant Staphylococcus aureus (VRSA), which was then purified using size exclusion and anion exchange chromatography. The hydrolytic activity of GDPD was evaluated on the non-physiological substrate bis(p-nitrophenyl) phosphate (BpNPP), which indicated functional activity of the enzyme. 79 drugs were evaluated for their inhibitory potential against GDPD enzyme by the colorimetric assay. Out of 79 drugs, 13 drugs, including tenofovir (1), adenosine (2), clioquinol (11), bromazepam (12), lamotrigine (13), sulfadiazine (14), azathioprine (15), nicotine (16), sitagliptin PO4 (17), doxofylline (18), clindamycin phosphate (19), gentamycin sulphate (20), and ceftriaxone sodium (21) revealed varying degrees of inhibitory potential with IC50 values in the range of 400 ± 0.007-951 ± 0.016 µM. All drugs were also evaluated for their binding interactions with the target enzyme by saturation transfer difference (STD-NMR) spectroscopy. 10 drugs demonstrated STD interactions and hence, showed binding affinity with the enzyme. Exceptionally, tenofovir (1) was identified to be a better inhibitor with an IC50 value of 400 ± 0.007 µM, as compared to the standard EDTA (ethylenediaminetetraacetic acid) (IC50 = 470 ± 0.008 µM). Moreover, molecular docking studies have identified key interactions of the ligand (tenofovir) with the binding site residues of the enzyme.

Diclofenac prodrugs nanoparticles: An alternative and efficient treatment for rheumatoid arthritis?

We have synthesized new lipidic prodrugs of diclofenac by grafting aliphatic chains (C10, C12, C16 and C18) to diclofenac through an ester bond. Their molecular formulas were confirmed through HR-MS and the formation of ester bond by FTIR and NMR spectroscopy. Nanoparticles of the different prodrugs were successfully formulated using emulsion evaporation method and DSPE-PEG2000 as the only excipient. All nanoparticles were spherical and had a size between 110 and 150 nm, PdI ≤ 0.2 and negative Zeta potential values from -30 to -50 mV. In addition, they were stable upon storage at 4 °C up to 30-35 days. The encapsulation efficiency of the prodrug was above 90 % independently of the aliphatic chain length grafted. Nanoparticles did not induce any toxicity on LPS-activated THP-1 cells up to a concentration of 100 µg/mL (equivalent diclofenac) whereas diclofenac sodium salt IC50 was around 20 µg/mL. Following incubation of nanoparticles with LPS-activated THP-1 cells, a dose dependent inhibition of TNF-α was observed comparable to standard diclofenac sodium. Based on in vitro studies representative nanoparticles, Prodrug 3 NPs (C16 aliphatic chain) were selected for further in vitro and in vivo studies. Upon incubation in murine plasma, Prodrug 3 NPs underwent an enzymatic cleavage and almost 70 % of diclofenac was released from nanoparticles in 8 h. In vivo studies on a collagen induced arthritis murine model showed contrasted results: on one hand Prodrug 3 NPs led to a significant decrease of arthritis score and of paw volume compared to PBS after the second injection, on the other hand the third injection induced an important hepatic toxicity with the death of half of the mice from the NP group. To promote the reduction of inflammation while avoiding hepatic toxicity using NPs would require to precisely study the No Observable Adverse Effect Level and the schedule of administration in the future.

A rapid colorimetric method for the detection of carminic acid in samples based on visible color change.

Carminic Acid (CA), an insect-derived red color, is widely used as a colorant and additive in food and non-food items. The detection of CA is of great concern since it is unacceptable for vegetarians and vegans consumers. Therefore, it is important for food authorities to have a rapid detection method for CA. We describe here a simple and rapid method for the qualitative detection of CA, using Pb2+ for complex formation. As a result, the sample solution shows a visible change from pink to purple (bathochromic shift) which could also be analyzed through a spectrophotometer at λmax = 605 nm. The structure of the CA-Pb2+ complex was also studied through advanced spectroscopic techniques. Moreover, the presence of iron results in the formation of a stable CA-Fe2+ complex without any significant color change, as Fe2+ has a stronger binding affinity with CA. Thus, sodium fluoride (NaF) was used to prevent CA-Fe2+ complex formation. Therefore, two methods were developed based on the absence (method I) and presence (method II) of NaF. The LOD and LOQ for the method I was 0.0025 and 0.0076 mg mL-1, and for method II, values were 0.0136 and 0.0415 mg mL-1, respectively. The methods were also validated by intra and inter-day analyses. A total of 45 commercials, including food and non-food samples, were screened for the detection of CA. The developed methods are applicable for the effective and rapid surveillance of CA in various samples without the use of high-tech instruments.

Glomerella fusarioides-catalyzed structural transformation of steroidal drugs mesterolone and methasterone, and anti-inflammatory activity of resulting derivatives.

Transformation of steroidal drug mesterolone (1) with Glomerella fusarioides yielded two new (17α-hydroxy-1α-methyl-5α-androstan-3-one-11α-yl acetate (2) and 15α-hydroxy-1-methyl-5α-androstan-1-en-3,17-dione (3)), and four known derivatives (15α,17ß-dihydroxy-1α-methyl-5α-androstan-3-one (4), 15α-hydroxy-1α-methyl-5α-androstan-3,17-dione (5), 1α-methyl-androsta-4-en-3,17-dione (6) and 15α,17ß-dihydroxy-1-methyl-5α-androstan-1-en-3-one (7). Similarly, G. fusarioides-catalyzed transformation of steroidal drug methasterone (8) afforded four new metabolites, 11α,17ß-dihydroxy-2,17α-dimethylandrosta-1,4-diene-3-one (9), 3a,11α,17ß-trihydroxy-2α,17α-dimethyl-5α-androstane (10), 1ß,3ß,17ß-trihydroxy-2α,17α-dimethyl-5α-androstane (11), and 11α,17ß-dihydroxy-2,17α-dimethylandrosta-1,4-diene-3-one (12). Structures of new derivatives were determined by using 1D-, and 2D-NMR, HREI-MS, and IR spectroscopic data. New derivative 3 was identified as a potent inhibitor of NÈ® production with the IC50 value of 29.9 ± 1.8 µM, in comparison to the standard l-NMMA (IC50 = 128.2 ± 0.8 µM) in vitro. In addition, methasterone (8) (IC50 = 83.6 ± 0.22 µM) also showed a significant activity comparable to new derivative 12 (IC50 = 89.8 ± 1.2 µM). New derivatives 2 (IC50 = 102.7 ± 0.5 µM), 9 (IC50 = 99.6 ± 5.7 µM), 10 (IC50 = 123.5 ± 5.7 µM), and 11 (IC50 = 170.5 ± 5.0 µM) showed a moderate activity. NG-MonomethylL-arginine acetate (IC50 = 128.2 ± 0.8 µM) was used as standared NO⋅- free radicals have an important role in the regulation of immune responses and cellular events. Their overproduction is associated with the pathogenesis of numerous ailments, such as Alzheimer's cardiac disorders, cancer, diabetes, and degenerative diseases. Therefore, inhibition of NÈ® production can help in the treatment of chronic inflammation and associated disorders. All derivatives were found to be non-cytotoxic to human fibroblast (BJ) cell line. The results presented here form the basis of further research for the development of new anti-inflammatory agents with improved efficacy through biotransformation approaches.

Isolation of secondary metabolites from Syzygium aromaticum (L.) Merr. & L.M.Perry. (cloves), and evaluation of their biological activities.

Phytochemical investigation of dried flower buds of Syzygium aromaticum (L.) Merr. & L.M.Perry. (clove) led to the isolation and identification of fourteen known compounds, oleanolic acid (1), betulinic acid (2), para methyl benzoic acid (3), sabrinic acid (4) eucalyptolic acid (5), nigricin (6), 3-O-trans-para-coumaroylmaslinic acid (7), methyl maslinate (8), maslinic acid (9), 3, 4, 5-trimethoxy-3',4'-O,O-methylideneflavellagic acid (10), lantanone (11) 3,4,3'-trimethoxyellagic acid (12), 11-oxo-oleanolic acid (13), and ß-sitosterol-3-O-ß-D-glucopyranoside (14). Their structures were identified by 1H NMR, 13C NMR, Mass spectroscopic techniques, and comparison with the literature data. Compounds 3, and 7-9 showed a strong mortality against root knot nematode, Meloidogyne incognita at 0.125% concentration after 72 hours (88-92% inhibition). Compound 4 showed a good anti-glycation activity with IC50 = 142.0 ± 1.8 µM when compared with standard, i.e. rutin (IC50 = 54.59 ± 2.20 µM). Compound 10 showed a comparable urease inhibitory activity (IC50 = 26.1 ± 0.19 µM) with the positive control thiourea (IC50 = 24.5 ± 0.34 µM).

New anti-inflammatory and non-cytotoxic metabolites of methylstenbolone obtained by microbial transformation.

A synthetic anabolic-androgenic steroid, methylstenbolone (1), was structurally transformed into a series of nine analogues, 2,17α-dimethyl-7α,17ß-dihydroxy-5α-androst-1-en-3-one (2), 2,17α-dimethyl-15ß,17ß-dihydroxy-5α-androst-1-en-3-one (3), 2,17α-dimethyl-6α,9α,17ß-trihydroxy-5α-androst-1-en-3-one (4), 2-methyl-17ß-hydroxy-17α-(hydroxymethyl)-5α-androst-1-en-3-one (5), 2-methyl-11ß,17ß-dihydroxy-17α-(hydroxymethyl)-5α-androst-1-en-3-one (6), 2-methyl-17ß-hydroxy-17α-(hydroxymethyl)-5α-androst-1-en-3,6-dione (7), 2-methyl-17ß-hydroxy-17α-(hydroxymethyl)-5ß-androst-1-en-3,6-dione (8), 2,17α-dimethyl-7ß,17ß-dihydroxy-5α-androst-1-en-3-one (9), and 2,17α-dimethyl-12ß,17ß-hydroxy-5α-androst-1-en-3,7-dione (10) by fungal cell suspension cultures, Macrophomina phaseolina and Cunninghamella blakesleeana for the first time. Among those, compounds 2-4 and 6-10 were identified as new. Herein, spectral data of metabolite 5 was reported for the first time. Their structures were elucidated by NMR, MS, UV, and IR spectroscopic methods. Substrate 1 (IC50 10.1 ± 0.3 µg/mL) was identified as a potent anti-inflammatory agent against nitric oxide (NO) production. Its transformed products 3 (IC50 as 27.8 ± 1.1 µg/mL) and 9 (26.9 ± 0.4 µg/mL) displayed good inhibition. Compounds 2 (IC50 = 45.9 ± 0.8 µg/mL) and 6 (IC50 = 36.6 ± 1.2 µg/mL) were also active moderately against NO production, in comparison to standard LNMMA (IC50 = 24.2 ± 0.8 µg/mL). Cytotoxicity assay showed 1 was active to cancer cell line MCF7 (IC50 = 12.26 ± 0.35 µg/mL), compared to the standard Doxorubicin having IC50 as 1.25 ± 0.11 µg/mL. However, it is also toxic to human normal cell line (BJ) with IC50 as 8.69 ± 0.02 µg/mL. More importantly, all transformed products are non-cytotoxic on BJ. Therefore, biotransformation can be an efficient approach to reduce the toxicity of methylstenbolone.

Drugs repurposing: An approach to identify new hits against anticancer drug target TFIIH subunit p8.

Drug repositioning is one of the most effective approaches towards drug discovery and development. It involves the identification of new therapeutic indications of existing drugs. The present study evaluated several drugs for their ability to modulate activity of the p8 subunit of TFIIH complex. Negative modulation of p8 subunit activity disrupts protein-protein interactions (PPIs) among the subunits of TFIIH complex, and thereby the TFIIH-associated functions. TFIIH complex has key role in the transcription and nucleotide excision repair activity in cancerous cells. TFIIH complex has emerged as a privileged drug target in anticancer research. Out of 60 drugs, amlopipine (13), diltiazem (16), gemfibrozil (19), levocitrizine dihydrochloride (20), losartan potassium (22), clorthalidone (24), and escitalopram (28) showed interactions with subunit p8 in the ligand-protein binding and chemical shift perturbation studies. The Kd values were found to be between 0.25 and 1 mM. These drugs also caused thermal destabilization of the subunit p8 by negatively shifting the melting temperature by ≥ 2 °C. Molecular docking studies indicated the interaction of these drugs with important residues of p8-p52 complex, such as Glu48, Lys51, Glu496, and Glu455 via non-covalent interactions. This study has thereby identified 7 drugs that can be investigated further as potential anticancer drugs.

Insight into isolation and elucidation of cytotoxic ergostanoids from the mushroom Sarcosphaera crassa (Santi) Pouzar: An edible mushroom.

Sarcosphaera crassa is a mushroom consumed in Europe and Anatolia after being cooked well. The cytotoxic activity of the extracts of unbaked S. crassa against MCF7, HT29, HeLa cancer cell lines and toxicity against PDF fibroblast healthy cell lines were studied using MTT assay. Acetone and methanol extracts of the mushroom exhibited significant cytotoxic activity. Further investigation of cytotoxic extracts afforded two new fatty acid sterols (1-2), a new ergosterol glycoside (4), and seven known compounds, including a fatty acid sterol (3), a steroid glycoside (5), two ergostanoids (6-7) and three sugars (8-10). These compounds were identified as brassicasteryl heptadecanoate (1), brassicasteryl palmitoleate (2), brassicasteryl linoleate (3), brassicasterol ß-ᴅ-xylofuranoside (4), brassicasterol ß-ᴅ-glucoside (5), brassicasterol (6), ergosterol-endoperoxide (7), mannitol (8), erythritol (9) and turanose (10). Among them, 7 exhibited a moderate cytotoxic activity against HeLa (IC50: 70.1 ± 2.0 µg/mL) and high activity against HT29 (IC50: 38.8 ± 0.9 µg/mL), and MCF7 (IC50: 62.9 ± 1.3 µg/mL) cancer cell lines. Compounds 4, 5, and 6 also exhibited significant cytotoxic activity against HT29 and MCF7. Moreover, all compounds exhibited weak toxicity against PDF healthy cell lines. This study indicates the potential use of Sarcosphaera crassa as a natural source of cytotoxic ergostanoids, which can be considered a dietary supplement for cancer prevention.

Isolation, characterization, and hepatoprotective properties of betulinic acid and ricinine from Tetracarpidium conophorum seeds (Euphorbiaceae).

The present study is to isolate and characterize betulinic acid and ricinine from T. conophorum seeds. Phytochemical investigation on hexane fraction of T. conophorum seeds led to the isolation of two compounds, Betulinic acid (1), and Ricinine (2). Betulinic acid and ricinine were screened against HepG2 cells and tested in vivo in CCl4 -induced experimental rats model. Results from this study showed that the compounds had hepatoprotective and cytotoxic activities. It was observed that betulinic acid inhibited HepG2 cell with percentage inhibition of 54% compared with standard doxorubicin (64%), while ricinine was inactive against HepG2 cell lines. Furthermore, molecular docking was carried out on betulinic acids and ricinine, with binding energies of -11.2 kcal/mol and -5.4 kcal/mol, respectively, indicating strong binding sites and interactions with Hepatitis B Virus DNA polymerase. Therefore, findings from this study suggest that betulinic acid possess cytotoxic and hepatoprotective properties, while ricinine exhibited hepatoprotection in CCl4 -induced liver damage. PRACTICAL APPLICATIONS: Medicinal plants contain unrestricted ability to make compounds that intrigue researchers in the quest for novel phyto-therapeutic drugs. The continuous exploration of new compounds in the medicinal plant is an auspicious strategy for the prevention of diseases. Therefore, the purpose of this research is to evaluate the cytotoxic and hepatoprotective compounds (betulinic acid and ricinine) isolated from T. conophorum seeds.

Biotransformation of contraceptive drug desogestrel with Cunninghamella elegans, and anti-inflammatory activity of its metabolites.

Biotransformation of an orally active contraceptive drug, desogestrel (1), with Cunninghamella elegans yielded a new metabolite, 13ß-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-17ß-ol-3,6-dione (2), along with five known metabolites, i.e., 13ß-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-3ß,6ß,17ß-triol (3), 13ß-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-6ß,17ß-diol-3-one (4), 13ß-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-17ß-ol-3-one (5), 13ß-ethyl-11-epoxy-18,19-dinor-17α-pregn-4-en-20-yn-17ß-ol-3-one (6), and 13ß-ethyl-11-methylene-18,19-dinor-17α-pregn-4-en-20-yn-10ß,17ß-diol-3-one (7). The structure of new metabolite 2 was elucidated by using 1H-, 13C-, and 2D-NMR, EI-, and HREI-MS, IR, and UV spectroscopic data. Compounds 1-7 were evaluated for anti-inflammatory activities, i.e., inhibition of T-cell proliferation, and pro-inflammatory cytokine (TNF-α). Compounds 1 (IC50 = 1.12 ± 0.03 µg/mL), 2 (IC50 = 1.15 ± 0.05 µg/mL), 3 (IC50 = 1.15 ± 0.05 µg/mL), 4 (IC50 = 1.40 ± 0.03 µg/mL), 5 (IC50 = 1.78 ± 0.08 µg/mL), and 6 (IC50 = 1.36 ± 0.07 µg/mL) were identified as potent inhibitors of T-cells proliferation, in comparison to the standard drug, prednisolone (IC50 = 3.51 ± 0.03 µg/mL). Compound 7 (IC50 = 6.18 ± 0.04 µg/mL) showed a good activity. In addition, substrate 1 (IC50 ≤ 1 µg/mL), and its metabolites 2 (IC50 = 4.1 ± 0.60 µg/mL), and 6 (IC50 = 6.8 ± 0.8 µg/mL) also showed a potent inhibition of pro-inflammatory cytokine (TNF-α) production, as compared to the standards drug, pentoxifilline (IC50 = 94.8 ± 2.1 µg/mL). Whereas compounds 3 (IC50 = 57.9 ± 7.6 µg/mL), and 5 (IC50 = 27.2 ± 6.8 µg/mL) showed a moderate inhibition of TNF-α production, while compounds 4 and 7 showed no inhibition. Compounds 1-7 were found to be non-cytotoxic to 3T3 normal cell line (mouse fibroblast).

A comparative profiling of oral cancer patients and high risk niswar users using FT-IR and chemometric analysis.

Oral cancer is one of the major cancer types, which has increased sustainably in Southeast Asian countries due to the extensive use of a variety of tobacco and betel nut products. The current study is focused on developing an easy, efficient and cost-effective method for plasma profiling of oral cancer patients and tobacco users in order to have a progressive picture towards oral cancer. For this purpose, the profiling of 147 plasma samples including 67 oral cancer patients' samples, 60 "niswar" (a dipping tobacco product) user samples, and 20 healthy controls using attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR), and chemometric analysis was carried out. Fingerprint region (500-1500 cm-1) of all three groups showed interesting variations in peaks pattern. From these observations, height ratios of two bands H1646/H1550 and H1080/H1024 with p value of 2.01 × 10-6 and 8.39 × 10-7, respectively, showed a pattern between healthy to oral cancer and "niswar" user samples. Chemometric analysis of the data showed a clean separation among the groups. PLS-DA and OPLS-DA models provided 87.7% and 89.5% classification rate, respectively. Area under the curve (AUC) for healthy control, oral cancer and "niswar" users were found to be 0.97, 0.95 and 0.92%, respectively. The results of the present study indicate that FT-IR spectroscopy, in conjunction with chemometric data, can be effectively used for the preliminary differentiation of plasma samples of oral cancer patients, "niswar" users and control samples of healthy persons.

Catalytic asymmetric synthesis of indole derivatives as novel α-glucosidase inhibitors in vitro.

Indole containing compounds have acquired conspicuous significance due to their wide spectrum of biological activities. Synthesis of a series of enantiomerically pure indole derivatives 3a-rvia Friedel-Crafts alkylation of indole 1 with enones 2a-r were described here. The products were isolated in a moderate to excellent yields (upto 89%) with excellent enantioselectivities (upto 99.9% ee). These compounds 3a-r were evaluated for their in vitro α-glucosidase inhibitory activity and some of them were identified as potent inhibitors (IC50 = 4.3 ±â€¯0.13-43.9 ±â€¯0.51 µM) with several fold higher activity than the clinically used α-glucosidase inhibitor, acarbose (IC50 = 840 ±â€¯1.73 µM). To the best of knowledge, this is the first report of the propanone substituted indole ring containing compounds by in vitro α-glucosidase enzyme inhibition.

Synthesis, and In Vitro and In Silico α-Glucosidase Inhibitory Studies of 5-Chloro-2-Aryl Benzo[d]thiazoles.

Twenty-five derivatives of 5-chloro-2-aryl benzo[d]thiazole (1-25) were synthesized and evaluated for their α-glucosidase (S. cerevisiae EC 3.2.1.20) inhibitory activity in vitro. Among them eight compounds showed potent activity with IC50 values between 22.1 ±â€¯0.9 and 136.2 ±â€¯5.7 µM, when compared with standard acarbose (IC50 = 840 ±â€¯1.73 µM). The most potent compounds 4, 9, and 10 showed IC50 values in the range of 22.1 ±â€¯0.9 to 25.6 ±â€¯1.5 µM. Compounds 2, 5, 11, and 19 showed IC50 values within the range of 40.2 ±â€¯0.5 to 60.9 ±â€¯2.0 µM. Compounds 1 and 3 were also found to be good inhibitors with IC50 values 136.2 ±â€¯5.7 and 104.8 ±â€¯9.9 µM, respectively. Their activities were compared with α-glucosidase inhibitor drug acarbose (standard) (IC50 = 840 ±â€¯1.73 µM). The remaining compounds were inactive. Structure-activity relationships (SAR) have also been established. Kinetics studies indicated compounds 2, 3, 10, 19, and 25 to be non-competitive, while 1, 5, 9, and 11 as competitive inhibitors of α-glucosidase enzyme. All the active compounds (1-5, 9-11, and 19) were also found to be non-cytotoxic, in comparison to the standard drug i.e., doxorubicin (IC50 = 0.80 ±â€¯0.12 µM) in MTT assay. Furthermore, molecular interactions of active compounds with the enzyme binding sites were predicted through molecular modeling studies.

FOXO1 targeting by capsaicin reduces tissue damage after testicular torsion.

Testicular torsion-related oxidative stress causes a sequential chain of DNA damage, lipid peroxidation and cell death that leads to the derangement in the sperm functions and infertility. Capsaicin that has been applied for pain relief and cancer prevention possesses antioxidant properties which can be exploited to confer cell survival under ischaemic testis damage. Wistar male rats weighing 150-200 g were randomly divided into four groups: (i) sham group (all procedures except torsion of testis), (ii) ischaemia group (TT group), (iii) three TT groups treated with different dose of capsaicin (TT + different doses of Cap) and (iv) three control groups treated with different doses of capsaicin (100, 500 and 1000 ug/ml). Capsaicin administration significantly decreased the expression of pro-apoptotic factors and increased the expression of anti-apoptotic factors. Likewise, the expression of FOXO1 is significantly increased by higher doses of the capsaicin. Histological assessment by H&E and TUNEL method also exhibited an improved testicular morphology and decreased apoptosis in testes. These results suggested clinical potential for capsaicin in treatment of testicular torsion by targeting FOXO1 and apoptotic pathways.

Synthesis of thiobarbituric acid derivatives: In vitro α-glucosidase inhibition and molecular docking studies.

Synthesis, structure, and evaluation of in vitro α-glucosidase enzyme inhibition of a new class of diethylammonium salts of aryl substituted thiobarbituric acid is described. This protocol is straight, environmentally benign and efficient, involving Aldol-Michael addition reaction in one pot fashion. The 3D chemical structures of the synthesized compounds were assigned based on spectroscopic methods and X-ray single crystal diffraction analyses. All synthesized compounds 3a-3n were evaluated for their in vitro α-glucosidase enzyme inhibitory activity, whereas acarbose was used as the standard drug (IC50=840±1.73µM). All tested compounds were found to possess varying degree of α-glucosidase enzyme inhibition activity with (IC50=19.46±1.84-415.8±4.0µM). Compound3i(IC50=19.4±1.84µM) exhibited the highest activity. To the best of knowledge this is the first report of the in vitro α-glucosidase enzyme inhibition by the diethylamonium salts of aryl substituted thiobarbituric acid. Furthermore, molecular docking studies of selected compounds were also performed to see interactions between active compounds and binding sites.

Prenylated flavonoids from the stems and roots of Tripterygium wilfordii.

Phytochemical investigation on the stems and roots of Tripterygium wilfordii led to the isolation and characterization of three new prenylated flavanones, tripteryols A-C (1-3), along with (±)-5,4'-dihydroxy-2'-methoxy-6',6″-dimethypyraro-(2″,3″:7,8)-6-methyflavanone (4), and ((2S)-5,7,4'-trihydroxy-2'-methoxy-8,5'-di(3-methyl-2-butenyl)-6-methylflavanone (5). Structures of the compounds 1-5 were elucidated using spectroscopic techniques, such as UV, IR, NMR (1D and 2D), and HRESI-MS. Tripteryols B (2) was found active in the antimicrobial assay against Cryptococcus neoformans, Pseudomonas aeruginosa, vancomycin-resistant Enterococcus faecalis (VRE) and methicillin-resistant Staphylococcus aureus (MRSA) with IC50 values in the range of 2.95-8.59µg/mL. Compounds 4 and 5 showed significant antimicrobial activities against C. neoformans, MRSA and Staphylococcus aureus with IC50 values in the range of 1.06-2.60µg/mL. Additionally, significant antimalarial activities of tripteryols A-B (1-2) against chloroquine-sensitive D6 and resistant W2 clones of Plasmodium falciparum were observed and none of the compounds 1-5 were cytotoxic to Vero cells.

Synthesis of pyrimidine-2,4,6-trione derivatives: Anti-oxidant, anti-cancer, α-glucosidase, ß-glucuronidase inhibition and their molecular docking studies.

This paper describes a facile protocol, efficient, and environmentally benign for the synthesis a series of barbiturate acid substituted at C5 position 3a-o. The desired compounds subjected in vitro for different set of bioassays including against anti-oxidant (DPPH and super oxide scavenger assays), anti-cancer, α-glucosidase and ß-glucuronidase inhibitions. Compound 3m (IC50=22.9±0.5µM) found to be potent α-glucosidase enzyme inhibitors and showed more activity than standard acarbose (IC50=841±1.73µM). Compound 3f (IC50=86.9±4.33µM) found to be moderate ß-Glucuronidase enzyme inhibitors and showed activity comparatively less than the standard d-saccharic acid 1,4-lactone (IC50=45.75±2.16µM). Furthermore, in sillico investigation was carried out to investigate bonding mode of barbiturate acid derivatives.

New adduct of abietane-type diterpene from Salvia leriifolia Benth.

A new adduct of abietane-type diterpene, salvialeriicone (1), was isolated from Salvia leriifolia Benth., along with a new chemical entity nor-abietane diterpene, 2-isopropyl-8,8-dimethyl-7,8-dihydrophenanthrene-1,4,5(6H)-trione (2). Their structures were determined using mass spectrometry, and 1D- and 2D-NMR spectroscopy.

Microbial transformation of oxandrolone with Macrophomina phaseolina and Cunninghamella blakesleeana.

Microbial transformation of oxandrolone (1) was carried out by using Cunninghamella blakesleeana and Macrophomina phaseolina. Biotransformation of 1 with M. phaseolina yielded four new metabolites, 11ß,17ß-dihydroxy-17α-(hydroxymethyl)-2-oxa-5α-androstan-3-one (2), 5α,11ß,17ß-trihydroxy-17α-methyl-2-oxa-androstan-3-one (3), 17ß-hydroxy-17α-methyl-2-oxa-5α-androstan-3,11-dione (4), and 11ß,17ß-dihydroxy-17α-methyl-2-oxa-5α-androstan-3-one (5). Whereas a new metabolite, 12ß,17ß-dihydroxy-17α-methyl-2-oxa-5α-androstan-3-one (6), was obtained through the microbial transformation of oxandrolone (1) with C. blakesleeana. The structures of isolated metabolites were characterized on the basis of MS and NMR spectroscopic data.

Leishmanicidal Triterpenes from Lantana camara.

Two new natural triterpenes, lantaninilic acid and lantoic acid, along with the known triterpenes lantadene A, and oleanolic, ursolic, betulinic, lantanolic, and camaric acid, were obtained from the aerial parts of Lantana camara through bioassay-guided isolation, monitoring the in vitro antileishmanial activity against promastigotes of Leishmania major. Oleanolic acid (3), ursolic acid (4), lantadene A (5), and lantanilic acid (7) showed significant leishmanicidal activities with IC50 values of 53.0, 12.4, 20.4, and 21.3 µM, respectively. The IC50 value of ursolic acid (4; 12.4 µM) was found to be comparable with that of the standard drugs, pentamidine (IC50 15.0 µM) and amphotericin B (IC50 0.31 µM). The in vitro activities of L. camara and its constituents against promastigotes of Leishmania major are reported here for the first time.