K. Nagaiah

An Efficient Knoevenagel Condensation Catalyzed by LaCl3.7H2O in Heterogeneous Medium

Abstract Knoevenagel condensation was carried out in absence of solvent with a mild Lewis acid Lanthanum(III) chloride, to prepare substituted alkenes. A systematic study of the reaction to establish the generality of the method has been undertaken with various aldehydes and active methylene compounds.

First examples of C-arylation of aziridines catalyzed by indium triflate

Abstract Aziridines react smoothly with arenes in the presence of a catalytic amount of indium triflate at ambient temperature to afford the corresponding β-aryl amine derivatives in excellent yields with high regioselectivity.

An eco-friendly synthesis of electrophilic alkenes catalyzed by dimethylaminopyridine under solvent-free conditions

Electrophilic olefins were synthesized in solvent‐free condition using DMAP (10%mol) as catalyst in excellent yield and E‐geometry. The various aldehydes which are aliphatic, aromatic, and heterocyclics underwent smoothly for Knoevenagel condensation with different active methylene compounds. #IICT Communication No. 030900.

Synthesis of new cis-fused tetrahydrochromeno[4,3-b]quinolines and their antiproliferative activity studies against MDA-MB-231 and MCF-7 breast cancer cell lines

New cis-fused tetrahydrochromeno[4,3-b]quinolines have been synthesized by intramolecular [4+2] imino-Diels-Alder reactions of 2-azadienes derived in situ from aromatic amines and 7-O-prenyl derivatives of 8-formyl-2,3-disubstituted chromenones in the presence of 20mol% Yb(OTf)(3) in acetonitrile under reflux conditions in good to excellent yields. The structures were established by spectroscopic data and further confirmed by X-ray diffraction analysis. These compounds were evaluated for their antiproliferative activity against MDA-MB-231 and MCF-7 breast cancer cells. The results showed that compounds 3e, 3f, and 3k exhibit significant antiproliferative activity against MCF-7 breast cancer cells and low inhibitory activity against MDA-MB-231 breast cancer cell lines. Compound 3h displayed activity as comparable to tamoxifen on both the cell lines.

Bi3+ CATALYZED REGIOSELECTIVE RING OPENING OF EPOXIDES WITH AROMATIC AMINES

ABSTRACT Epoxides undergo the facile ring opening with anilines to afford the corresponding β-amino alcohols in excellent yields by bismuth trichloride in acetonitrile at ambient temperature.

Triphenylphosphine–Iodine: An Efficient Reagent System for the Synthesis of Nitriles From Aldoximes

Abstract A wide range of aldoximes were smoothly converted to the corresponding nitriles with triphenylphosphine–iodine. IICT Communication No. 050106.

Efficient Synthesis of β‐Amino Alcohols Catalyzed by Niobium Pentachloride: Regioselective Ring Opening of Epoxides with Aromatic Amines

Abstract Epoxides undergo a rapid ring‐opening reaction with aromatic amines catalyzed by niobium pentachloride under mild reaction conditions. All the reactions were carried out at room temperature to afford the corresponding β‐amino alcohols in excellent yields and with high regioselectivity. IICT Communication No. 050916

Efficient protocol for reductive amination of aldehydes and ketones with sodium borohydride in an ionic liquid/H2O system

Abstract The imines were generated in situ from carbonyl compounds and amines, which undergo smooth reduction with sodium borohydride in an ionic liquid/H2O solvent system. The reaction conditions were very mild and neutral to afford the corresponding highly functionalized amines in excellent yields. IICT Communication No. 041013.

[bmim]PF6/CuBr: a novel and recyclable catalytic system for the synthesis of propargyl amines

A novel and efficient method has been developed for the synthesis of propargyl amines in a one-pot operation from aldehydes, amines and alkynes by using copper(I) bromide immobilized in ionic liquids. The ionic liquid containing catalyst can be recovered and recycled in three to four subsequent runs with gradual decrease in activity

Synthesis of novel chromeno-annulated cis-fused pyrano[3,4-c]benzopyran and naphtho pyran derivatives via domino aldol-type/hetero Diels–Alder reaction and their cytotoxicity evaluation

New chromeno-annulated cis-fused pyrano[3,4-c]benzopyran and naphtho pyran derivatives have been synthesized by domino aldol-type reaction/hetero Diels-Alder reaction generated from o-quinone methide in situ from 7-O-prenyl derivatives of 8-formyl-2,3-disubstituted chromenones with resorcinols/naphthols in the presence of 20 mol% ethylenediamine diacetate (EDDA), triethylamine (2 mL) as co-catalyst in CH3CN under reflux conditions in good yields. The structures were established based on spectroscopic data, and further confirmed by X-ray diffraction analysis. The results showed that compounds 4h and 4j exhibited very potent cytotoxicity against human cervical cancer cell line (HeLa). Compound 4h displayed good inhibitory activity against both breast cancer cell lines, MDA-MB-231 and MCF-7. Further, the compound 4i exhibited good cytotoxicity against only MDA-MB-231, and compound 4j showed promising activity against human lung cancer cell line, A549 with IC50 value of 2.53±0.07 μM, which was comparable to the standard doxorubicin (IC50=1.21±0.1 μM).