Publications by authors named "Khursheed A Bhat"

Betulinic acid isolated from Platanus orientalis bark was modified in a one pot reaction to furnish twelve urea derivatives.The synthesized derivatives were tested against an array of cancer cell lines, colon HCT-116, breast MCF-7, pancreatic MIA PaCa-2 and prostate PC-3 cancer cell lines. Among the synthesized compounds BA1 exhibited potent anti-cancer activity with IC50 of 0.

View Article and Find Full Text PDF

Diverse betulinic acid-dithiocarbamate conjugates were designed and synthesized a two-step reaction at room temperature. Among the fourteen dithiocarbamate analogs of betulinic acid, DTC2 demonstrated the best antifungal activity against , with a minimum inhibitory concentration (MIC) of 4 μg mL, achieving 99% fungicidal activity at the same concentration. These compounds were found to be ineffective against common Gram-negative and Gram-positive pathogens, suggesting their specificity to fungi.

View Article and Find Full Text PDF

Sclareol, a bioactive diterpene alcohol isolated from , was subjected to structural modification and cytotoxic evaluation. Boron-Heck-coupled analogs of manoyl oxide were prepared from sclareol in a two-step reaction scheme. In the first step manoyl oxide was prepared from sclareol using cerium (IV) ammonium nitrate.

View Article and Find Full Text PDF

An efficient strategy towards stereoselective amidation of alkynes is reported. The given method features operational simplicity, excellent functional group tolerance, broad substrate scope and fast kinetics to furnish -enamides. Moreover, the method was successfully applied for the facile synthesis of the natural products lansiumamide A, lansiumamide B and -alatamide.

View Article and Find Full Text PDF

Novel sarracinic acid derivatives bearing triazole or N-heterocyclic moiety were prepared two separate reaction schemes. The triazoles and the N-heterocyclic derivatives were synthesised using standard click chemistry approach and amination of 2-bromoethyl ester of sarracinic acid respectively. All the synthesised derivatives were screened for neuroprotective activity against corticosterone induced impairment in neuroblastoma cell line SH-SY5Y.

View Article and Find Full Text PDF

An unprecedented, one-step strategy for the synthesis of 5-(methylthio)pyridazin-3(2)-one derivatives has been developed through iodine triggered deaminative coupling of glycine esters with methyl ketones and hydrazine hydrate in DMSO. These transformations in the absence of hydrazine helped to generate different 3-methylthio-4-oxo-enoates in good yields. Notably, DMSO played multiple roles such as oxidant, methylthiolating reagent, and solvent.

View Article and Find Full Text PDF

An efficient strategy towards -formylation of amides and oxidation of indolines to isatins is described. This method employs readily available (NH)SO, I, and DMSO. The given method features operational simplicity, excellent functional group tolerance, broad substrate scope, and fast kinetics.

View Article and Find Full Text PDF

Aim: To evaluate the antimicrobial capability of sclareol and its derivatives against Staphylococcus aureus and its Methicillin-resistant strain (MRSA).

Methods And Results: A new series of Boron-Heck-coupled sclareol analogues were prepared by structural modifications at the C-15 terminal double bond of sclareol using ultrasonication. The structural modifications were designed to keep the stereochemistry of all the five chiral centres of sclareol intact.

View Article and Find Full Text PDF

Senecio graciliflorus DC root extract was studied for secondary metabolite composition following the bioactivity-guided isolation technique. The ethyl acetate extract of Senecio graciliflorus root yielded nine chemical constituents: 3,4-di-tert-butyl toluene, stigmasterol, β-sitosterol, 2β-(angeloyloxy)furanoeremophilane, gallic acid, 2β-{[(Z)-2-hydroxymethylbut-2-enoyl]oxy}furanoeremophilane, 1-hydroxypentan-2-yl-4-methylbenzoate, sarcinic acid, and sitosterol 3-O-β-D-glucopyranoside. The structures of the chemical constituents were elucidated on the basis of spectral data analysis in the light of literature.

View Article and Find Full Text PDF

An unusual quinazoline alkaloid (1) was obtained when 2-aminobenzaldehyde was refluxed with pyrrolidine in ethanol for 12 h. The synthesized compound was characterized using spectral data analysis augmented with X-ray and literature precedent. Single crystal analysis depicted four conformations differing slightly in bond angles and bond lengths.

View Article and Find Full Text PDF

The aim of the present study was to isolate and evaluate the antimicrobial potential of soil actinomycetes of Kashmir Himalayas. The secondary metabolites of actinomycetes are the prominent source of antibiotics. A total of 121 morphologically different actinomycete strains were isolated and screened for antimicrobial activity against various human pathogens.

View Article and Find Full Text PDF

Diosgenin, a promising anticancer steroidal sapogenin, was isolated from Dioscorea deltoidea. Keeping its stereochemistry rich architecture intact, a scheme for the synthesis of novel diosgenin analogues was designed using Cu (I)-catalysed alkyne-azide cycloaddition in order to study their structure-activity relationship. Both diosgenin and its analogues exhibited interesting anti-proliferative effect against four human cancer cell lines viz.

View Article and Find Full Text PDF

Using a click chemistry approach, a series of gallic-acid-1-phenyl--[1,2,3]triazol-4-ylmethyl esters was synthesized to develop more effective antioxidants. The results of DPPH screening indicate that few of the synthesized analogs display better antioxidant effect compared to the standards. Among all, compounds, and displayed highest DPPH radical scavenging effect with IC values as low as 6.

View Article and Find Full Text PDF

Arglabin belongs to guaianolide class of sesquiterpene lactones, isolated from Artemisia species. The molecule bears a 5,7,5-tricyclic ring system having five contiguous stereo centers in which the two five membered rings are trans-annulated. Arglabin shows promising antitumor activity against different tumor cell lines.

View Article and Find Full Text PDF

Sclareol, a promising anticancer labdane diterpene, was isolated from Salvia sclarea. Keeping the basic stereochemistry-rich framework of the molecule intact, a method for the synthesis of novel sclareol analogues was designed using palladium(II)-catalyzed oxidative Heck coupling reaction in order to study their structure-activity relationship. Both sclareol and its derivatives showed an interesting cytotoxicity profile, with 15-(4-fluorophenyl)sclareol (SS-12) as the most potent analogue, having IC50 = 0.

View Article and Find Full Text PDF

This article presents the isolation, quantification and antioxidant evaluation of bioactive principles from Epimedium elatum. LC-MS guided isolation technique was applied for the separation of target constituents. Three isolates; magnoflorine, chrysin and dibenzylideneacetone (DBA) were isolated for the first time from E.

View Article and Find Full Text PDF

Using β-sitosterol and stigmasterol as precursor materials, a concise and efficient hemisynthesis of aromatase inhibitors: testololactone and testolactone was accomplished in a well-established reaction scheme. It involves highly effective Oppaneur oxidation of both β-sitosterol as well as stigmasterol to generate the required enone moiety in ring 'A' of the desired steroid system. The Oppaneur oxidation products of both β-sitosterol and stigmasterol were then subjected to oxidative cleavage of the side chain to produce 4-androstene-3,17-dione.

View Article and Find Full Text PDF

The essential oil of different parts of Senecio graciliflorus DC was obtained by hydrodistillation and analysed by GC-FID and GC-MS for the first time. A total of 17, 20, 19 and 17 constituents were identified comprising 99.90, 95.

View Article and Find Full Text PDF

A convenient and modular synthesis involving diastereoselective Michael addition followed by regioselective Huisgen 1,3-dipolar cycloaddition reaction was carried out to furnish 1,4-disubstituted-1,2,3-triazoles of Ludartin. This reaction scheme involving Michael addition followed by regioselective Huisgen 1,3-dipolar cycloaddition reaction leading to the formation of triazolyl analogs is being reported for the first time. All the triazolyl products were characterised using spectral data analysis.

View Article and Find Full Text PDF

The hexane extracts of both shoot and root parts of Artemisia amygdalina Decne displayed potent cytotoxic effects. Phytochemical analysis of these active extracts led to the isolation of six cytotoxic constituents, viz., Ergostadien-3β-ol (1), ludartin (2), 5-hydroxy-6,7,3',4'-tetramethoxyflavone (3) (from shoot) and trans-matricaria ester (4), diacetylenic spiroenol ether (5) and cis-matricaria ester (6) (from root) for the first time from this plant.

View Article and Find Full Text PDF

Phytochemical investigation of the aerial parts of Rhododendron lepidotum yielded 8-[2',6'-dimethoxy-4'-(1″,2″,3″-trihydroxy-propyl)-phenyl]-7-hydroxy benzopyranone (1), 3-O-β-d-glycopyranosyl betulinic amide (2) and 8-hydroxy-7,7'-oxydicoumarin (4) and five known compounds. Among the known molecules, betulinic amide (3) was earlier reported as a semi-synthetic product. The structures of new molecules 1, 2 and 4 were elucidated on the basis of extensive spectroscopic investigations (1D NMR, 2D NMR and mass spectrometry).

View Article and Find Full Text PDF

Diverse amino analogs of Ludartin, a cytotoxic guaianolide and a position isomer of an anticancer drug, Arglabin were prepared through Michael type addition at its highly active α-methylene-γ-lactone motif. The semisynthetic derivatives were subjected to sulphorhodamine B cytotoxicity assay against a panel of four different human cancer cell lines viz. lung (A-549), leukemia (THP-1), prostate (PC-3) and colon (HCT-116) to look into structure-activity relationship.

View Article and Find Full Text PDF

The essential oil from the leaves of Juglans regia L. (Juglandaceae) growing wild in Kashmir (India) was obtained by hydrodistillation and analysed by a combination of capillary GC-FID and GC-MS. A total of 38 compounds, representing 92.

View Article and Find Full Text PDF