Direct synthesis of 2-(cycloalkylamino)-3,4-substituted thiophenes via selective deprotonation-cyclization of aroyl ketene N,S-acetals

Acyclic and cyclic aroyl ketene N,S-acetals undergo regioselective deprotonation-cyclization via dipole stabilized carbanion in the presence of LDA/THF to afford the corresponding 2-(cycloalkylamino)-4-aryl or 3,4-annelated thiophenes in moderate to good yields

Synthesis and anti–microbial activity of 1,2,3–triazole tethered nitroguiacol ethers

Nitro aromatic/nitrophenols have been widely distributed in nature and are mostly isolated from marine microorganisms and had shown a broad spectrum of anti–microbial activities against a wide range of microbial pathogens. The objective of the present work is to Synthesize some new 1,2,3–triazole tethered nitroguiacol ethers and evaluated of their anti–bacterial and anti–fungal activities. A focused library of 1,2,3-triazole tethered nitroguiacol ethers were prepared by employing Cu (I) catalyzed click chemistry reaction and evaluated for their antimicrobial activities by broth microdilution method. Among the tested compounds, compounds 8e, 8f, 8g, and 8i exhibited broad–spectrum activity against selected pathogenic strains, with the MIC of 8 µg/mL for gram–positive bacteria (Staphylococcus aureus), 16 µg/mL for Pseudomonas aeruginosa (gram–negative bacteria), and Candida species, respectively. Future investigations with this class of compounds may lead to the development of potential candidates for antimicrobial drug discovery.Â

ESTIMATION OF PRIMIDONE IN COMMERCIAL DOSAGE FORMS USING A SIMPLE AND CONVENIENT HPLC METHOD

ABSTRACT A simple fast and precise reverse phase high performance liquid chromatographic method has been developed for the determination of Primidone Tablets. A symmetry (5µ, 150 x 4 .6mm column) in isocratic mode with methanol: Water (50:50) as mobile phase. The Flow rate is1.0ml/min and effluent is monitored at 210nm

Synthesis and Lewis acid assisted rearrangement of novel donor-acceptor substituted cyclopropanes: highly stereoselective [4+1] annulation approach to substituted and spiro cyclopentene derivatives

The cyclopropanes 2a-h having 4-(bismethylthio)butadienyl moiety as donor group, which are easily obtained by regioselective cyclopropanation of vinylogous ketene dithioacetals 1a-h with oxodimethylsulphonium methylide, undergo facile Lewis acid assisted vinylcyclopropyl rearrangement to afford substituted and spiro cyclopentenes 3a-h in good yields

Anionic [4+2] cycloaddition reactions of indole-2,3-dienolate with dienophiles: a facile regiospecific route to substituted carbazoles

Indole 2,3-dienolate derived by deprotonation of 1,2-dimethylindole-3-carboxaldehyde is shown to be useful 1,4-dipole synthon (anionic indolo-2,3-quinodimethane) which undergoes facile cycloaddition with wide range of dienophiles affording substituted carbazoles in highly regiospecific fashion

Design, Synthesis and Biological Studies of Tetrazole Fused olpidemimidazopyridines

New tetrazole fused imidazopyridine derivatives (12a–j) were developed to exploit their cytotoxic activity towards cancer cell lines-MCF7, A549, and MDA-MB-231, utilizing MTT reduction assay with doxorubicin as standard drug. The compounds 12 h and 12j demonstrated strong anticancer activity bearing IC50 values 1.44 µM and 1.33 µM against A549 cell line

Catalysis by Amberlyst A-21: A Greener Approach to 4,5,6,7-Tetrahydro-1H-indazol-3(2<i>H</i>)-ones via Construction of Cyclohexanones

<div><p></p><p>The 4,5,6,7-tetrahydro-1H-indazol-3(2H)-one derivatives have been synthesized in good yields via a two-step method in a single pot. The initial step involved the construction of cyclohexanone ring from aromatic aldehydes and β-ketoester in i-PrOH using an inexpensive and reusable catalyst (i.e., Amberlyst A-21) under mild reaction conditions. The utility of this catalyst has been demonstrated in synthesizing a range of cyclohexanone derivatives. The catalyst can be recovered and recycled, which makes this procedure simple, convenient, economically viable, and environmental friendly.</p> <p>[Supplementary materials are available for this article. Go to the publisher's online edition of <i>Synthetic Communications</i>® for the following free supplemental resource(s): Full experimental and spectral details.]</p> </div

Wang Resin Catalyzed Green Synthesis of 1,8-Dioxo-octahydroxanthene Derivatives and their in Silico/in vitro Evaluation against SIRT1

Because of important role in cancer, sirtuins especially the SIRT1 is viewed as an interesting pharma- cological target for developing potential anticancer agents. Based on our previous studies on sirtuin in- hibitory potential of 1,8-dioxodecahydroacridines we extended our efforts towards exploring the struc- turally relevant 1,8-dioxo-octahydroxanthene derivatives for the similar pharmacological evaluations. The targeted 1,8-dioxo-octahydroxanthenes were conveniently accessed via the sonochemical condensation of a range of (het)aryl aldehydes with 5,5-dimethyl-1,3-cyclohexanedione in water. All these reactions were catalyzed by the sulphonic acid-functionalized Wang resin (Wang-OSO3H) that was recovered and reused for several times without major loss of its catalytic efficiency. This eco-friendly approach afforded the desired products in good to high (87–96%) yields. Initial in silico docking of 1,8-dioxo-octahydroxanthene derivatives possessing a 6-membered aryl ring at the C-9 position into SIRT1 suggested inferior binding interactions in most of the cases (total estimated energy \u3c 82 kcal/mol). While two of these compounds e.g. 3a and 3l showed H-bond interactions through a carbonyl group with the residue ILE347 and ASP348 and a pi-sigma and pi-pi interaction with the residue PHE297 and PHE273 through a methyl group and the C-9 phenyl ring, respectively the size of the C-9 aryl ring seemed to have played a key role in the binding interactions of this class of compounds. Indeed, replacing the 6-membered aryl ring at C-9 by a 5-membered heteroaryl ring e.g. furan or thiophene afforded compounds that showed superior inter- actions (total estimated energy -98.18 and -89.9 kcal/mol) with SIRT1 in silico. The furan analogue 3q showed three H-bond interactions through its two carbonyl groups with the residues HIS363, ILE347 and ASP348 and a pi-pi interaction through the C-9 furan ring. The good in silico interactions of compound 3q were further supported by the initial in vitro assay when this compound showed encouraging inhibition (\u3e 87%) of SIRT1 at 10 μM. The in silico and in vitro studies identified compound 3q along with two other analogues for further pharmacological studies

Design and synthesis of novel indole-quinoxaline hybrids to target phosphodiesterase 4 (PDE4)

A series of novel hybrid molecules were designed rationally by connecting an indole moiety with a quinoxaline ring through a linker as potential inhibitors of PDE4. Their design was validated initially in silico by performing docking studies using a representative molecule. Subsequent synthesis of a focused library of related hybrid molecules was accomplished using Pd/CACu mediated coupling-cyclization as a key step. Some of the synthesized compounds showed PDE4 inhibition in vitro and one of them appeared to be promising