Padmaja Ambati

• Professor (Assistant) at Sri Sathya Sai Institute of Higher Learning

Background: Processing wastes that are generated at industrial and house hold level are a huge concern. Utilization of these by-products and their bioactive compounds is a blooming industry at present. This study has been designed to unleash the potential of such by-product (stalks) and their possible application. Methods: In order to use plant by-...

Background: Muntingia calabura (Panama berry), is a wholesome fruit borne to a multipurpose tree. It is one of the tropical fruits native to Mexico and Central America.. Muntingia calabura plant is being widely cultivated in India, South Asia, Malaysia, Indonesia and Philippines. This tropical fruit, is known for its nutritional, anti-microbial and...

Products from some of the natural resources such as spices continue to be used in pharmaceutical preparations either as crude extracts, fractions, pure compounds or analogous compounds from highly active isolated compounds. Research into their role as contributors of dietary polyphenols known to possess a number of properties associated with increa...

A variety of N-((1,3-diphenyl-5-aryl-1H-pyrazol-4-yl)sulfonyl)thiophene-2-carboxamides (7) and N-((5-aryl-3-phenylisoxazol-4-yl)sulfonyl)thiophene-2-carboxamides (8) were prepared from (E)-N-(arylethenesulfonyl)thiophene-2-carboxamides (4) adopting 1,3-dipolar cycloaddition of nitrile imines and nitrile oxides generated from araldehyde phenylhydraz...

A new class of methylthio linked pyrimidinyl 1,3,4-oxadiazoles, 1,3,4-thiadiazoles and 1,2,4-triazoles were prepared under conventional and ultrasound irradiation methods. All the compounds were obtained in higher yields and in shorter reaction times in ultrasound irradiation method when compared with the conventional method. The title compounds we...

The bis and tris heterocycles-benzoxazolyl/benzothiazolyl/benzimidazolyl quinazolines linked by sulfur and/or nitrogen were prepared from 2,4-dichloroquinazoline and benzazolyl-2-thiol/benzazolyl-2-amine and studied their antibacterial activity. The nitro-substituted sulfur-linked bisbenzothiazolylquinazoline (12f), bisbenzimidazolylquinazoline (13...

Some new di(indolyl)thiazolylpyrazoles were prepared from the synthetic intermediate E-1,3-di(1H-indol-3-yl) prop-2-en-1-one under ultrasonication and studied their cytotoxic and antioxidant activities. All the compounds were screened for in vitro cytotoxic activity on three cancer cell lines. The compound 7e exhibited appreciable anticancer activi...

A variety of bisazolylsulfonyl amines have been prepared from azolylsulfonyl chlorides and azolylsulfonamides and their antimicrobial activity studied. The chloro substituted bisthiazolylsulfonyl amines exhibit pronounced antibacterial activity against B. subtilis. The unsubstituted and chloro substituted bisimidazolylsulfonyl amines show promising...

A new class of mono and bis heterocycles - styryl sulfonylmethyl-1,3,4-oxadiazolyl/1,3,4-thiadiazolyl amines, pyrrolyl sulfonylmethyl-1,3,4-oxadiazolyl/1,3,4-thiadiazolyl amines and pyrazolyl sulfonylmethyl-1,3,4-oxadiazolyl/1,3,4-thiadiazolyl amines were prepared from the synthetic intermediate Z-styrylsulfonylacetic acid adopting simple and well...

Thiazolyl pyrazoles and isoxazoles were prepared and their antimicrobial activity studied. Chloro- and nitro-substituted thiazolyl isoxazoles were potential antibacterial agents against Staphylococcus aureus, and nitro-substituted thiazolyl pyrazole was a potential antifungal agent against Aspergillus niger.

The Michael acceptor 1,4-bis-(E)-2-(arylsulfonylvinyl)benzene was exploited to prepare a new series of bis heterocycles-(1,4-phenylene)bis(arylsulfonylpyrrole) and (1,4-phenylene)bis(arylsulfonyl pyrazole). All of the compounds were tested for antioxidant activity. Amongst the tested compounds, 1,4-bis-(E)-2-(arylsulfonylvinyl)benzene (5) was found...

The gem cyano ester functionality in double Michael adduct, 4-carboethoxy-2-carbomethoxy-4-cyano-3,5-diaryl-tetrahydro[2H]thiopyran-1,1-dioxide 1 has been exploited to develop three different types of spiro heterocycles viz., spiro pyrhnidine, pyrazole and isoxazole derivatives in the presence of appropriate nucleophiles.

Some new 3,4-disubstituted pyrroles and pyrazoles were prepared from the synthetic intermediate (E)-1-(4-(mchlorobenzyloxy)- 3-methoxyphenyl)-3-(4-aryl)prop-2-en-1-one on treatment with tosylmethyl isocyanide and diazomethane. All the target compounds were evaluated for antimicrobial activity. The chloro substituted pyrroles and pyrazoles (5c, 7c)...

The nucleophilic reactivity of 2-chloro-5-(4-phenyl-1H-1,2,3-triazol-1-yl) benzenamine 5 was studied with different reagents under ultrasonication.

A new class of amino derivatives of 3-(4-phenyl-1,2,3-triazolyl)benzamine have been prepared using different electrophilic reagents under ultrasonication and microwave methodologies.

A series of amine linked bis- and tris-heterocycles were prepared from heteroaryl cinnamamides and tested for antimicrobial activity. The compounds 11c and 12c exhibited excellent antibacterial activity while 12a and 12c displayed excellent antifungal activity.

A variety of pyrimidinyl benzoxazoles, benzothiazoles and benzimidazoles linked by thio, methylthio and amino moieties were prepared and studied their antimicrobial and cytotoxic activities. The compound pyrimidinyl bis methylthio benzimidazole 22 was a potent antimicrobial agent particularly against Staphylococcus aureus (29 mm, MIC 12.5 μg/mL) an...

via Sm(III)-catalyzed cyclocondensation reactions of the corresponding heterocyclic sulfonylacetic acid ester (I) with 2-aminoethanol, 2-aminoethanethiol or ethylenediamine, respectively

A new class of bis-heterocyclic sulfamoyl acetamides was prepared and studied their antimicrobial activity. The chloro substituted thiazolyl imidazolylsulfamoyl acetamide 6i is found to be a potential antimicrobial agent against Pseudomonas aeruginosa and Penicillium chrysogenum.

A new class of (1,4-phenylene)bis(arylsufonylpyrazoles and isoxazoles) were synthesized by 1,3-dipolar cycloaddition of nitrile imines and nitrile oxides to the 1,4-bis((E)-2-(arylsulfonyl)vinyl)benzenes in the presence of chloramine-T. Compound 7f exhibited pronounced antimicrobial activity.

from styrene-ω-sulfonamides adopting a 1,3-dipolar cycloaddition strategy

A new class of oxazolinyl/thiazolinyl/imidazolinyl-benzo- xazoles/benzothiazoles/benzimidazoles have been prepared by exploiting the respective heterocyclic sulfonyl acetic acid methyl ester functionality with different nucleophiles using samarium(III) chloride.

Alternative routes for the synthesis of the title compounds (IV) and (VI) are described.

A new class of pyrrolyl and pyrazolyl sulfonamides was prepared from styrene-ω-sulfonanilides by treatment with tosylmethyl isocyanide and diazomethane, respectively.

A new class of five-membered heterocycles oxazolines and thiazolines have been prepared by multistep, one-pot and microwave irradiation methodologies. The microwave method provides an excellent approach for the safe, rapid, inexpensive and simple synthesis of oxazolines and thiazolines.

In the title compound, C18H16ClN3O5S2, the dihedral angles between the oxadiazole ring and the phenyl and chloro­benzene rings are 23.4 (2) and 45.4 (2)°, respectively. The C—S—N—C and Cox—C—S—C (ox = oxadiazole) torsion angles are 89.3 (5) and −69.1 (3)°, respectively. A short intra­molecular C—H⋯O contact closes an S(6) ring. In the crystal, mol­...

a b s t r a c t A new class of sulfone linked bis heterocycles viz., pyrrolyl/pyrazolyl arylaminosulfonylmethyl 1,3,4-oxadiazoles, 1,3,4-thiadiazoles, and 1,2,4-triazoles were prepared and tested for antimicrobial activity and cytotoxicity. The chloro-substituted compounds 5c, 8c and 14c showed comparable anti-bacterial activity to chloramphenicol...

The sulfonyl activated (E)-olefin (I) is used as synthon for novel pyrrole and pyrazole derivatives by 1,3-dipolar cycloaddition of tosylmethyl isocyanide (II) and diazomethane (IV), respectively.

This work was undertaken to explore the potential of fruit waste materials as sources of natural antioxidants. Kernels of four varieties of mangoes of Indian origin were studied. Kernels were extracted with five different solvents, tested for extraction efficiency and total phenolic content (TPC). As the methanol proved to be the best solvent, it w...

Natural antioxidants have gained considerable interest in recent years for their role in preventing the autooxidation of fats, oils and fat containing food products. In the present study, three leaf extracts viz., beetle leaf (BLE), curry leaf (CLE) and guava leaf (GLE) were used as sources of natural antioxidants. Different solvents like methanol,...

A new class of amido linked bis heterocycles viz., pyrrolyl/pyrazolyl-oxazoles, thiazoles and imidazoles were prepared by 1,3-dipolar cycloaddition of TosMIC and diazomethane to the respective cinnamamide derivatives and screened for antimicrobial activity. The chlorosubstituted imidazolyl cinnamamide (6c) is the most potential antimicrobial agent...

A new class of oxazolyl/thiazolylsulfonylmethyl pyrazoles (10-13) and isoxazoles (14, 15) were prepared from the synthetically vulnerable intermediate E-styrylsulfonylacetic acid methyl ester (1) and studied their antioxidant activity.

With a view to obtaining biologically interesting heterocycles, the new class of the heterocyclic compounds (IV), (V), (VII), (IX), and (XI) are prepared by using facile, simple and well established synthetic methods.

An increase in the demand for natural additives has shifted the attention from synthetic to natural antioxidants. Antioxidative components from pomegranate peel were extracted by using different solvents like methanol, ethanol, acetone, chloroform and ethyl acetate. All the extracts were tested for Total phenolic content (TPC) and the methanol whic...

The present study aimed at determination of the effect of peel extracts of four mango varieties (baneesha, malgoa, totapuri and neelam) in inhibiting the oxidative rancidity of refined, bleached and deodourised soybean oil (RBDSBO) samples. Total phenolic content was estimated by Folin-Ciocalteau reagent. Baneesha peel extracts (BPE), malgoa peel e...

For Abstract see ChemInform Abstract in Full Text.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A new class of amino-pyrazolones, amino-isoxazolones, amino-hydroxypyrimidinones, amino-mercaptopyrimidinones and imino-pyrimidinediones are prepared by the cyclocondensation of Michael adduct, ethyl-3,4-diarylsulfonyl-2-cyanobutyrate with different nucleophiles.

For Abstract see ChemInform Abstract in Full Text.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Exploiting lanthanide chemistry and 1,3-dipolar cycloaddition technology, title compounds (V) are prepared as a new class of substituted pyrroles.

A new class of oxadiazoles is prepared by treating aminosulfonylacetic acids with different carboxylic acid hydrazides. Interconversion of oxadiazoles to thiadiazoles is carried out with thiourea. The compounds are screened for antimicrobial and antioxidant activities.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A new class of sulfone linked pyrrolyl oxazolines and thiazolines were synthesized from E-arylsulfonylethenesulfonylacetic acid methyl ester and studied their antimicrobial and antioxidant activities.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A new class of heterocycles, substituted pyrazoles, isoxazoles, pyrimidines, thioxopyrimidines were prepared from Michael adducts, 2-(1,2-diaroylethyl)malononitrile and 2-(1,2-diarylsulfonylethyl)malononitrile by cyclocondensation with appropriate nucleophiles. The lead compounds were screened for the antimicrobial and antioxidant activities.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A new class of 1,3,4-oxadiazoles were prepared from acid hydrazides on treatment with different carboxylic acids in the presence of phosphorus oxychloride. Interconversion of oxadiazoles to thiadiazoles and triazoles was carried out with appropriate reagents. The antimicrobial and cytotoxic activities of compounds 7a-d to 12a-d were tested. Compoun...

A new class of 2-oxazolines and 2-thiazolines 9/10 and 13/14 are prepared by base promoted cyclization of 3-aryl-N(2-hydroxyethyl)-4-(arylsulfonyl) butanamide/3-aryl-S-(2-aminoethyl)-4-(arylsulfonyl)butanethioates with NaH in THF. 9/10 and 13/14 are also obtained by one pot methodology using samarium(III) chloride.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A variety of sulfone derivatives including three dimethyl arylsulfonyl malonates (1-3), two bis-(arylethenesulfonyl)-vinyl benzenes (4 and 5) and a sulfone triazole (6) were evaluated for their anti-inflammatory as well as tumor cells growth inhibitory activities in vitro. The sulfone derivatives 1, 2, 3 and 6 significantly and dose-dependently inh...

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

A novel class of bis selena and/or thiadiazoles were prepared by the reaction of semicarbazones of 3,6-dithiaoctahydrophenanthrene- 1,8-dione, 3,6-dithiaoctahydroanthracene-1,8-dione and 3,7-dithiaoctahydroanthracene-1,5-dione with SeO2 and SOCl2, respectively. The latter, in turn, were obtained from 1,2-, 1,3- and 1,4-xylylenedimercaptoacetic acid...

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

A new class of keto-linked bis heterocycles have been prepared by 1,3-dipolar cycloaddition of tosyl methyl isocyanide, nitrile imines and nitrile oxides to unsymmetrical bischalcones.

For Abstract see ChemInform Abstract in Full Text.

Mono- and bis-pyrazolines and isoxazolines have been prepared by the 1,3-dipolar cycloaddition of nitrile imines and nitrile oxides to 3,3′-[1,4-/1,3-phenylene]bis[1-aryl-2-propenone] in the presence of chloramine-T.

For Abstract see ChemInform Abstract in Full Text.

A new class of spiro-pyrimidines, pyrazoles and isoxazoles are prepared by nucleophilic reaction of 3,5-diaroyl-2,6-diaryl-piperidine-4,4-dicarbonitrite (1), 3,5-diaroyl-2,6-diaryl-tetrahydropyran-4,4-dicarbonitrile (2) and 3,5-diaroyl-2,6-diaroyl-tetrahydrothiopyran-4,4-dicarbonitrile (3) with urea, N,N'-dimethyl urea, thiourea, hydrazine hydrate...

The reaction of phenacylsulfonylacetic acid methyl ester and styrylsulfonylacetic acid methyl ester with hydrazine hydrate gives unusual products, 1,1-dioxo-6-phenyl-1,2,4,7-tetrahydro-1λ6-[1,4,5]thiadiazepin-3-one and 1,1-dioxo-6-phenyl-1λ6-[1,4,5]thiadiazepan-3-one instead of the expected acid hydrazide.

2,4,6-Trisubstituted heterocycles are prepared by the functionalization of gem-disubstituents and keto functionalities in 1,5-diaryl-3,3-dimethoxycarbonyl- 1,5-pentane-dione (1) and 1,5-diaryl-3-cyano-3-ethoxycarbonyl-1,5-pentanedione (4).

The cycloaddition of diazomethane, cyclocondensation of hydrazine hydrate, and cyclopropanation of TMSOI to 1-aroyl-2-styrylsulfonylethenes were studied and different novel products thereby obtained were characterized with spectral parameters. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:155–159, 2003; Published online in Wiley InterScience (w...

The bifunctional bis pyrazolines and bis isoxazolines have been prepared from 1-aroyl-2-styrylsulfonylethenes and 1-arylsulfonyl-2-styrylsulfonylethenes.

1,5-Diphenyl-3,3-dicyano-1,5-pentanedione has been used to incorporate N, O, S to obtain 1,4-dihydropyridine, 4 H -pyran, and 4 H -thiopyran, which in turn serve as precursors for the synthesis of novel spiro heterocycles. All the compounds were characterized by IR and NMR spectral data.

Mono and bis pyrazolines were prepared by the cycloaddition and cyclocondensation reactions of diazomethane and hydrazine hydrate with bis olefinic systems.

The reaction of 1,5-diaryl-3-methyl-1,4-pentadien-3-one with araldehyde phenylhydrazone/araldoxime in the presence of chloramine-T proceeds regiospecifically in MeOH and regioselectively in AcOH leading to mono- and bis-pyrazolines/ isoxazolines.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The mass spectra of some pyrazole and isoxazole derivatives have been studied under electron impact conditions. It has been observed that the activated olefins and araldehyde phenylhydrazone/araldoxime ions are the precursor ions in the cleavage process of the above molecules.

The bifunctional heterocyclic sulfones containing selenadiazoles/thiadiazoles and pyrazolines/isoxazolines have been prepared from phenacyl E-styryl sulfones.

Different heteroatoms viz., N, S & Se have been incorporated into 2-arylethenyl-2′-arylethynyl sulfones by nucleophilic reaction with benzylmine, hydrogen sulfide and sodium hydrogen selenide.

The cycloaddition of diazomethane to 1-aroyl-2-arylsulfonylethenes (1) and 1,2-bis (arylsulfonyl) ethenes (IV) under different conditions led to a variety of pyrazolines and pyrazoles. The reactivity of pyrazolines was also studied by pyrolysis, nitrosation and acylation.

Cis 2,6-Diphenyltetrahydrothiapyranone (1) was subjected to Wittig reaction to generate exocyclic double bond (2a-c). Cycloaddition of nitrile oxides and nitrile imines to the latter led to a novel spiro tetrahydrothiapyranoisoxazolines (3a-f) and spiro tetrahydrothiapyranopyrazolines (4a-f).

6,8- Diaryl - 6,7-dihydrocarbazole (4), 6,8- diaryl - 6,7,8,9, - terahydrocarbazole (7), 6,8- diaryl carbazole (8) were obtained from the Fischer indole cyclization of 6 - carbethoxy- 3,5- diarylcyclohex- 2-en-1-one (1).

Some new trans-aryl cyclopropyl sulfones (II) have been prepared by the cycloaddition of dimethylsulfoxonium methylide to trans-styryl aryl sulfones (I) by two different methods. It is observed that the reaction in presence of a phase transfer catalyst proceeds in a facile manner.

Antimicrobial activity of newly synthesized 5,7-diaryl(-4-alkyl)trihydro thiapyrano [3,4-d][1,2,3] selena/thiadiazoles, 5,7-diaryl(-4-alkyl)trihydropyrano[3,4-d][1,2,3]selena/thiadiazoles and 5,7-diaryl(-4-alkyl)trihydroselenapyrano[3,4-d][1,2,3]selena/ thiadiazoles was investigated. Generally, selenium containing compounds and their halogen substi...