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A high quantity of (1R, 5S)-4-Ethyl-6,6-dimethyl-3-(phenysulfonyl)bicyclo(3.1.1)hept-3-en-2-one is derived from (+)-nopinone. This complex is alkylated using reactive alkyl bromides which reveal the participation of allyl bromide. Gamma-alkylated derivatives are obtained in adequate quantities from the complex in an extracyclic stereocontrolled method. 4,4-disubstituted nopinoes are obtained when enone is added to carbon nucleophiles preceding desulfonylation. Enol acetates are obtained with the cleavage of the cyclobutane ring of nopinoes, with no loss of optical purity. 4,4-disubstituted nopinones and cyclobutanes can be formed by chemically converting gamma-alkylated products.

The Mannich reaction of methylsilyl enol ether with aryl�aldimine proceeded in the presence of a catalytic amount of lithium chloride in dimethylformamide at room temperature. The reaction was mild enough to apply to aldimines having the AcO, TBDMSO, or MeS group. Microwave irradiation accelerated the reaction substantially to reduce reaction time. [ABSTRACT FROM AUTHOR]

Purpose: To develop and validate a new, simple, sensitive, rapid, cost-effective and accurate reverse phase-high performance liquid chromatography (RP-HPLC) method for the determination of aprepitant (APT) in capsule dosage form. Methods: The method developed for the determination of APT in capsule formulation involved using RP-HPLC which incorporated a C18 column 250 x 2.5 mm i.d, 5 μm particle size, in isocratic mode, with mobile phase comprising of methanol: water in the ratio of 90:10 (v/v). The flow rate was 1 mL/min and the detection was monitored at 220 nm. The total run time was 10 min and the column was maintained at ambient temperature. Results: APT was eluted in the given mobile phase with a retention time (tr) of 4.473 min. The linearity for the quantification of APT was 0.1 - 10 μg/mL (R2 =0.989, Y= 33032x + 71501) with coefficients of variation (based on mean peak area for six replicate injections) in the range 0.04 to 0.132. The limits of detection and of quantification were 0.028 and 0.094 μg/mL, respectively. Recovery of the method was 99.56 - 100.5 % while the relative standard deviation (RSD) of intra-day and inter-day precision was 0.85 and 1.05, respectively. System precision and method precision were 0.013 and 1.400 %, respectively. The specificity data of the proposed method indicated that excipients in the capsules did not interfere with the drug peak. Furthermore, the well-shaped peaks buttressed the specificity of the method. Conclusion: The proposed RP-HPLC method is simple, sensitive, rapid, cost-effective and accurate for the determination of APT in both bulk materials and pharmaceutical dosage forms. [ABSTRACT FROM AUTHOR]

In vitro study was carried out to determine the antibacterial activity of root extracts of Berberis lycium by using various solvents for extraction. The methanolic root extract showed higher inhibitory effect as compared to the other solvent extracts, against the mixed culture of human pathogenic bacteria viz., Pseudomonas sp., Escherchia coli, Streptococcus sp. and Staphylococcus sp. However, methanolic extract when used separately were less effective compared to Gentamycin and Amoxicillin showing inhibition zone of 10, 11 and 12 against Staphylococcus, Pseudomonas sp. and E. coli respectively. [ABSTRACT FROM AUTHOR]

A simple, sensitive, and specific LC-ESIâMS/MS method for quantification of Montelukast (MO) in human plasma using Montelukast-d(6) (MOD6) as an internal standard (IS) is discussed here. Chromatographic separation was performed on YMC-pack pro C(18), 50 x 4.6 mm, S-3 Îm column with an isocratic mobile phase composed of 10mM ammonium formate (pH 4.0):acetonitrile (20:80 v/v), at a flow-rate of 0.8 mL min(â1). MO and MOD6 were detected with proton adducts at m/z 586.2â568.2 and 592.3â574.2 in multiple reaction monitoring (MRM) positive mode respectively. MO and MOD6 were extracted using acetonitrile as precipitating agent. The method was validated over a linear concentration range of 1.0â800.0 ng mL(â1) with correlation coefficient (r(2)) â 0.9996. The intraday precision and accuracy were within 1.91â7.10 and 98.32â99.17. The inter-day precision and accuracy were within 3.42â4.41% and 98.14â99.27% for MO. Both analytes were found to be stable throughout three freeze-thawing cycles, bench top, and autosampler stability studies. This method was utilized successfully for the analysis of plasma samples following oral administration of MO (5 mg) in 31 healthy Indian male human volunteers under fasting conditions.

A simple, precise, accurate and rapid high performance thin layer chromatographic method has been developed and completely validated for the estimation of trandolapril in bulk and pharmaceutical dosage forms. Quantification of trandolapril was carried out with percolated silica gel 60F(254) as stationary phase using mobile phase consisting of Chloroform: Methanol: Acetic acid (8:1.5:0.5 v/ v/ v) and scanned in Absorbancei Reflectance mode at 212 nm using Camag TLC scanner 3 with WinCAT software. The R(f) value of trandolapril was found to be 0.54 (±0.03). The proposed method has permitted the quantification of trandolapril over the linearity range of 25-150 ng/spot and its percentage recovery was found to 99.7%. The intraday and inter day precision were found to be 1.26% and 1.4%, respectively. The limit of detection and the limit of quantification were found to be 18 ng/ spot and 54 ng/ spot, respectively. The proposed method can be successfully applied for the estimation of drug content of different marketed formulations simultaneously on a single plate and provides a faster and cost effective quality control tool for routine analysis of trandolapril as bulk drug and in tablet dosage forms.