Synthesis and antitumor evaluation of some 1,3,4-oxadiazole-2(3<Emphasis Type="Italic">H</Emphasis>)-thione and 1,2,4-triazole-5(1<Emphasis Type="Italic">H</Emphasis>)-thione derivatives

A series of 1,3,4-oxadiazole-2-thione and 1,2,4-triazole-5-thione derivatives have been successfully synthesized and studied for their antitumor activity. These compounds were prepared from carboxylic acids and chiral aminoacid esters. The prepared compounds were evaluated for their cytotoxicity against cancer in vitro using hydroxyurea (HU) as positive control. A fair number of compounds were found to have significant antitumor activity. To study the molecular basis of interaction and affinity of binding of the target molecules, all the compounds were docked into the ATPase domain of TP-II and tubulin using Schrödinger.     

Synthesis and antimicrobial activity of novel 5-amino-4-cyano-<Emphasis Type="Italic">1H</Emphasis>-pyrazole and quinazolin-4(<Emphasis Type="Italic">3H</Emphasis>)-one derivatives

New substituted aroylhydrazones (4a-f) were synthesized from the acid hydrazide (3) and the corresponding aldehyde or aldose. 5-Amino-4-cyano-1H-pyrazole derivatives (6a-f) were prepared by the reaction of the aroylhydrazones (4a-f) with malononitrile. The synthesized compounds were tested for antimicrobial activity against various bacteria and fungi and showed moderate to high inhibition activities. Compounds incorporating a sugar moiety as well as a pyrazolyl ring in their structure displayed the highest antimicrobial activity.     

Synthesis and biological evaluation of some functionalized 1<Emphasis Type="Italic">H</Emphasis>-1,2,3-triazole tethered pyrazolo[3,4-<Emphasis Type="Italic">b</Emphasis>]pyridin-6(7<Emphasis Type="Italic">H</Emphasis>)-ones as antimicrobial and apoptosis inducing agents

A series of novel molecular hybrids containing pyrazole, pyridinone and 1,2,3-triazoles have been synthesized by one-pot four-component reaction of Meldrum’s acid, substituted aryl azides, 4-(prop-2-yn-1-yloxy)aryl aldehyde and 3-methyl-1-phenyl-1H-pyrazol-5-amine using L-proline as a basic organocatalyst besides CuSO₄.5H₂O and sodium ascorbate as catalysts for click chemistry in PEG-400 as a highly efficient and green media. Apoptosis studies have been carried out on ovarian follicles of goat (Capra hircus) and in vitro antibacterial activity has been done against six strains namely Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa and antifungal activity against two yeast strains namely, Candida albicans and Saccharomyces cerevisiae.     

Synthesis and anti-inflammatory activity evaluation of novel 3-alkyl-6-(4<Emphasis Type="Italic">H</Emphasis>-1,2,4-triazol-4-yl)-3,4-dihydro-2<Emphasis Type="Italic">H</Emphasis>-benzo[<Emphasis Type="Italic">e</Emphasis>][1,3]oxazine derivatives

To discover new compounds with anti-inflammatory activity, a series of novel 3-alkyl-6-(4H-1,2,4-triazol-4-yl)-3,4-dihydro-2H-benzo[e][1,3]oxazine derivatives were synthesized and their structures were confirmed by spectroscopic techniques. In vivo anti-inflammatory activity of the synthesized compounds was determined using the xylene-induced mouse ear edema model. 3-Heptyl-6-(4H-1,2,4-triazol-4-yl)-3,4-dihydro-2H-benzo[e] [1,3]oxazine and 3-p-tolyl-6-(4H-1,2,4-triazol-4-yl)-3,4-dihydro-2H-benzo[e][1,3]oxazine demonstrated higher anti-inflammatory activity (74.04?% and 64.99?%, respectively) at 0.5?h after intraperitoneal administration than the reference drug ibuprofen (62.65?%). Further, the time of peak effect after oral administration was 4?h for both compounds. Our results identify new compounds with anti-inflammatory activity in vivo that may have improved safety/side effect profiles relative to the currently approved nonsteroidal anti-inflammatory drugs.     

Microwave-assisted synthesis,molecular docking and antimicrobial activity of novel 2-(3-aryl,1-phenyl-1<Emphasis Type="Italic">H</Emphasis>-pyrazol-4-yl)-8<Emphasis Type="Italic">H</Emphasis>-pyrano[2,3-f]chromen-4-ones

An efficient synthetic protocol of microwave-assisted synthesis of some novel 2-(3-aryl,1-phenyl-1H-pyrazol-4-yl)-8H-pyrano[2,3-f]chromen-4-ones 6a–j in excellent yields starting from 3-(3-aryl,1-phenyl-1H-pyrazol-4-yl)-1-(5-hydroxy-2H-chromen-6-yl)-propenones 5a–j was described. This approach offers the advantages of short reaction time (3–5 min), mild reaction conditions, high yields (80–88 %) and convenient operation. All the synthesized compounds were tested in vitro for their antimicrobial activity. The compounds 5h (Ar = 3-ethoxyphenyl), 6c (Ar = 4-chlorophenyl), 6e (Ar = 4-hydroxyphenyl) and 6i (Ar = 3,4-methoxyphenyl) were found to be potent against tested bacterial strains, and compounds 5g (Ar = 4-ethoxyphenyl), 6c (Ar = 4-chlorophenyl) and 6i (Ar = 3,4-methoxyphenyl) were found to be potent against tested fungal strains. The final compounds were subjected to molecular docking studies for the inhibition of enzyme DNA gyrase. The in silico molecular docking results are matching with the in vitro antimicrobial studies, and they may be considered as good inhibitor of DNA gyrase.     

Synthesis and antimicrobial screening of <Emphasis Type="Italic">N</Emphasis>-(1-methyl-1<Emphasis Type="Italic">H</Emphasis>-pyrazole-4-carbonyl)-thiourea derivatives

In the search of bioactive molecules in the class of functionally 4-substituted pyrazolic compounds, a series of N-(1-methyl-1H-pyrazole-4-carbonyl)-thiourea derivatives were prepared by addition of various substituted anilines to 1-methyl-1H-pyrazole-4-carbonyl isothiocyanate. The new thioureides and the intermediary compounds were characterized by spectroscopic data and elemental analyses and were evaluated for antibacterial and antifungal activities.     

Synthesis and <Emphasis Type="Italic">in Vitro</Emphasis> cytotoxic activities of 2-alkyl-2,3-dihydro-1<Emphasis Type="Italic">H</Emphasis>-2,6-diazacyclopenta[<Emphasis Type="Italic">b</Emphasis>]anthracene-5,10-diones

A series of 2-alkyl-2,3-dihydro-1H-2,6-diazacyclopenta[b]anthracene-5,10-diones (4a–f) was synthesized and their in vitro cytotoxic activities were evaluated against six human cancer cell lines (HCT15, SK-OV-3, SNB19, A549, MCF7 and MCF7/ADR). They all appeared to be less potent than doxorubicin against all doxorubicin sensitive human cancer cell lines tested. However, these compounds retained considerable cytotoxic activity against the doxorubicin-resistant cell line MCF7/ADR, implying their therapeutic potential to treat doxorubicin-resistant tumors. The most active compound 4c was equipotent with doxorubicin against HCT15 cell line.     

Synthesis,characterization and <Emphasis Type="Italic">in vitro</Emphasis> anti-tumor activities of novel 9-ethyl-9<Emphasis Type="Italic">H</Emphasis>-purine derivatives

Newer series of 9-ethyl-9H-purine derivatives (EPD) were synthesized and screened for their efficacy in inhibiting the proliferation of various tumor cells in vitro. We evaluated the effects of EPD against HeLa, SiHa, CaSki (human cervical cancer cells), LM8, LM8G7 (murine osteosarcoma cells), OVSAHO and SKOV-3 (human ovarian cancer cells). The chemical structures of the EPD were confirmed by ¹H NMR and LCMS analyses. The inhibitory effects of EPD were studied by using trypan blue exclusion, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and TetraColor One reagents. Furthermore, SAR studies revealed that the presence of trifluoromethoxy and trifluromethyl group in 4b and 4g, respectively are responsible for the significant activity of the EPD against cervical cancer cells and the presence of isopropoxy group in 4f has influence in inhibiting the proliferation of osteosarcoma and ovarian cancer cell types.     

Synthesis and evaluation of some novel <Emphasis Type="Italic">N</Emphasis>-substituted rhodanines for their anticancer activity

Novel N-substituted rhodanines 2a–g were synthesized by conventional and microwave-assisted methods and tested for their anticancer activity. Structure–activity relationship of the synthesized rhodanine 2a–g as antiproliferative agents was investigated. The results revealed that all the seven compounds showed potent antiproliferative activity in a concentration-dependent manner on leukemic cell line K562. Among the tested compounds, 2b was found to be more potent when compared by trypan blue and MTT assay. IC₅₀ values of 2b using trypan blue and MTT assay were found to be 11.1 and 20.3 µg/ml, respectively. A dose-dependent increase in the LDH release was also observed upon treatment with 2a–g. Cell cycle analysis revealed that 2b affects DNA replication and leads to accumulation of cells in G ₀ and decline of G ₂/M, G ₁ and S phases which indicates apoptosis. The selective cytotoxic activity against human chronic myelogenous cell line (K562), via apoptosis, suggests that compound 2b is a promising scaffold for the development of novel anticancer drug.     

Synthesis and biological testing of (5<Emphasis Type="Italic">Z</Emphasis>)-2-aryl-5-arylmethylidene-3,5-dihydro-4<Emphasis Type="Italic">H</Emphasis>-imidazol-4-ones as antimitotic agents

Compounds interacting with cell protein tubulin and microtubules represent an important type of antimitotic agents. A series of tubulin-targeted 2-aryl-4-benzoyl-imidazoles were reported to possess high cytotoxicity, and so, we prepared a series of structural isomers of these to be evaluated as antimitotic agents. The synthesis of the novel (Z)-2-aryl-5-arylmethylidene-3,5-dihydro-4H-imidazol-4-ones involved coupling of substituted hippuric acids with aromatic aldehydes. Subsequent conversion of the resulting oxazolones to the corresponding imidazolones was carried out under microwave irradiation in the presence of urea and ammonium acetate. The cytotoxicity of the majority of the compounds to human epithelial carcinoma cancer cell line A549 was in the sub-micromolar range and was found to be more sensitive to the substituents on the 5-arylmethylidene fragment than on the 2-aryl ring in general. The cytotoxicities of the synthesized compounds were lower than those of the previously reported isomeric 2-aryl-4-benzoyl-imidazoles, and the basic structure–activity relationships in the isomeric pairs were different. Synthesized (5Z)-5-[(4-bromophenyl)methylidene]-2-(4-methylphenyl)-3,5-dihydro-4H-imidazol-4-one, which had the highest cytotoxicity (IC₅₀ ~ 440 nM) in the series of novel compounds, had a definite cytostatic effect on the A549 cells, but its antiproliferative properties were not linked to action on the microtubules. This would be an interesting lead compound for additional investigation into the mechanism of cytostatic action, and further structural optimization.     

Synthesis,antibacterial and antifungal activities of novel thiazolidinyl sulfonamides of quinazolin-4(3<Emphasis Type="Italic">H</Emphasis>)ones

Some novel derivatives of quinazolinone including 2-[2-(2, 6-dichlorophenyl)amino]phenylmethyl-3-{4-[2-(substituted phenyl)-4-oxo-thiazolidin-3-yl]phenylsulfonamido-1-yl}-6-bromoquinazolin-4(3H)ones (4a – 4l) were prepared from 2-[2-(2, 6-dichlorophenyl) amino]phenylmethyl-3-{[4-(N-substituted arylidene)phenyl]-sulfonamide-1-yl}-6-bromo quinazolin-4(3H)ones (3a – 3l). Twenty four synthesized compounds were screened in vitro for their antibacterial and antifungal activities. Minimum inhibitory concentration (MIC) values of all the twenty four compounds were determined. Some of these compounds exhibited significant antimicrobial activity.     

Synthesis and antidepressant activity of 5-(benzo[b]furan-2-ylmethyl)-6-methylpyridazin-<Emphasis Type="Italic">3</Emphasis>(<Emphasis Type="Italic">2H</Emphasis>)-one derivatives

A new series of pyridazin-3-one derivatives were designed, synthesized and evaluated for their preclinical antidepressant effect on Swiss mice. Among the series, compounds 6c, 6d and 6f exhibited significant activity profile in forced swimming test. Compounds 6c and 6d were most efficacious, which at dose of 50 mg kg^?1 reduced the time of immobility by 42.85 and 38.09 %, respectively, as compared to the standard drug fluoxetine which reduced the immobility time by 45.23 % at the dose of 32 mg kg^?1. All the test and standard compounds were administered orally 60 min before the test. Interestingly, all active compounds did not cause any significant alteration of locomotor activity in mice as compared to control, indicating that the hybrids did not produce any motor impairment effects. The results indicate that pyridazin-3(2H)-one derivatives may have potential therapeutic value for the management of mental depression.     

Synthesis and evaluation of <Emphasis Type="Italic">p</Emphasis>-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-dialkyl substituted chalcones as anti-cancer agents

Several new N,N-dialkyl substituted chalcones (chalconoids or benzylideneacetophenones) have been synthesized via the condensation of corresponding N,N-dialkylbenzaldehyde with various aryl methyl ketones. All the chalcones have been synthesized from readily available and cheap starting materials under environmentally benign conditions in very high yields without work up and column chromatographic purification. Synthesized compounds have been tested for their biological activity against pathogenic microorganisms such as Escherichia coli, Bacillus subtilis, and Mycobacterium smegmatis. Anti-cancer activity of these compounds has also been tested against multiple myeloma (RPMI-8226) and human mammary adenocarcinoma (MCF-7) cell lines. The most hydrophilic molecules 23 and 24 showed very good anti-cancer activity against MCF-7 cell lines at low micro-molar concentrations. All the compounds have also been evaluated for their activity against Beta-secretase 1 enzyme. One of the synthesized compounds showed Beta-secretase 1 enzyme inhibition activity at micro-molar concentration.     

<Emphasis Type="Italic">NAT2</Emphasis>,<Emphasis Type="Italic"> CYP2C9</Emphasis>,<Emphasis Type="Italic"> CYP2C19</Emphasis>, and<Emphasis Type="Italic"> CYP2E1</Emphasis> genetic polymorphisms in anti-TB drug-induced maculopapular eruption

Purpose  

It has been suggested that drug-metabolizing enzymes might play important roles in the development of anti-tuberculosis drug (ATD)-induced maculopapular eruption (MPE), as in ATD-induced hepatitis. We investigated the associations between the genetic polymorphisms of drug-metabolizing enzymes and ATD-induced MPE.     

Mercuric chloride catalyzed synthesis of some anticancer 2-aryl-2,3-dihydroquinizolin-4(1<Emphasis Type="Italic">H</Emphasis>)-ones

A series of ten 2,3-dihydroquinizolin-4(1H)-one derivatives were synthesized by ethanol-mediated condensation of anthranilamide with various aryl aldehydes in presence of catalytic amount of mercuric chloride (HgCl₂). The temperature of the reactions was maintained at 60?°C for good yield of the products. The highlights of the method include use of lab grade of chemicals as reagents and ease of work up in obtaining the product with high purity. Out of ten derivatives synthesized, three compounds 3f, 3i, and 3j are new and all the compounds were evaluated for their cytotoxic activity against six cancer cell lines. The compounds 3b (IC50: 26.1?µg mL^?1), 3c (42.7?µg mL^?1) ,and 3e (31.1?µg mL^?1) have shown activity against the cell line MDA-MB-231. Compounds 3b, 3c, 3d, 3e, and 3g showed significant total growth inhibition (TGI) values against the cell line MDA-MB-231 and compound 3j showed good TGI value against the cell line PANC 1. Compounds were also screened for their antibacterial activity and antioxidant activity by DPPH method.     

MDMA induces <Emphasis Type="Italic">Per1</Emphasis>, <Emphasis Type="Italic">Per2</Emphasis> and <Emphasis Type="Italic">c-fos</Emphasis> gene expression in rat suprachiasmatic nuclei

Rationale  

±3,4-Methylenedioxymethamphetamine (MDMA, ‘ecstasy’) is a psychoactive drug that has marked effects on the serotonergic system. Serotonergic agonists are known to interact with the circadian pacemaker located in the suprachiasmatic nuclei (SCN).     

Biological activity of <Emphasis Type="Italic">Entada phaseoloides</Emphasis> and <Emphasis Type="Italic">Entada rheedei</Emphasis>

The aim of our study is to find functional compounds from natural resources. We focus on plants grown in tropical areas, especially Madagascar and Thailand, because they have unique flora and are expected to contain interesting compounds. We review the functional compounds of the seed kernels of Entada phaseoloides and E. rheedei and their biological activities such as anti-proliferation and melanogenesis inhibitory properties, etc.