Showing papers by "P. Manivel published in 2009"

Synthesis of 3 substituted isoquinolin-1-yl-2-(cycloalk-2-enylidene) hydrazines and their antimicrobial properties

Abstract: New hydrazine derivatives were synthesized via reaction between 1, 3 cyclic diketones and hydrazinoisoquinoline derivatives. The reaction proceeded smoothly in ethanol under reflux temperature and furnished products in excellent yields (76–87%). The products have been purified and fully characterized by spectroscopy techniques. The compounds 8a-c showed good bacterial inhibition against Bacillus cerus and 8d-f showed good antifungal activity against Candida albicans.

Evaluation of intermolecular interactions in thioisocoumarin derivatives: the role of the sulfur atom in generating packing motifs

Abstract: Five derivatives of thioisocoumarin bearing aromatic and nonaromatic ring systems have been synthesized and characterized to unravel the importance of interactions due to the presence of a sulfur atom in generating packing motifs in the crystalline state. Apart from the well characterized interactions like C–H⋯S, a CS⋯π interaction is found in one of the case studies. The importance of such interactions in crystal structure packing along with routine C–H⋯π and π⋯π interactions is examined in the context of overall stability in the molecular assembly. The CS⋯π interactions in comparison to CO⋯π interactions have been analyzed using the Cambridge Structural Database (CSD).

Isocoumarin Thioanalogues as Potential Antibacterial Agents

Abstract: A series of 3-substituted-1H-isochromene-1-thiones (3) were prepared by the reaction of 3-substituted isocoumarins (2) with Lawesson's reagent in the presence of toluene under a nitrogen atmosphere. The antimicrobial activities of the newly synthesized products were measured using Gram-negative (Escherichia coli, Salmonella typhi, and Proteus mirabilis) and Gram-positive bacteria (Staphylococcus aureus and Bacillus cereus). Synthesized thioanalogue of isocoumarins showed good antibacterial activity against Proteus mirabilis.

Synthesis of Some New 2,4-Disubstituted Hydrazinothiazoles and 2,5-Disubstituted Thiazolidinones

Abstract: A series of hydrazinothiazoles has been synthesized by the condensation of thiosemicarbazones and α-bromoketones. Similarly the hydrazinothiazolidiones were prepared by the condensation of thiosemicarbazone and α-bromoesters. The newly synthesized compounds were characterized by NMR and LCMS studies.

Synthesis of 2-(2-(hydroxymethyl)phenyl)ethanol derivatives as potential antibacterial agents

Abstract: Reaction of 3-substituted isocoumarins (1a-h) with excess of sodium borohydride in methanol gave the corresponding 2-(2-(hydroxymethyl)phenyl)ethanol derivatives (2a-h). Antimicrobial activities of synthesized compounds were measured, using Gram-negative (Escherichia coli, Salmonella typhi, Proteus mirabilis) and Gram-positive bacteria (Bacillus cereus, Staphylococcus aureus). Key words: Isocoumarin, sodium borohydride, diol, antimicrobial properties. e-mail: nawaz_f@yahoo.co.in. INTRODUCTION Synthesis of variety of compounds like carbocyclic, heterocyclic compounds and various aromatic compounds can be effected from isocoumarins intermediates. 1 The hydroxyl structural moiety was found in numerous pharmaceutically active compounds and therefore represents an interesting template for combinatorial as well as medicinal chemistry. 2 In particular phenylethanol derivatives have good antifungal properties. 3, 4 An increasing number of new isocoumarins in nature and increasing importance of diol derivatives have stimulated our researcher group a continued interest for synthesis of 2-(2-(hydroxymethyl)phenyl)ethanols from the precursor isocoumarins. Recently, several methods have been reported for the synthesis of diols such as palladium catalyzed reactions, electrophilic aromatic substitution, cyclization of 2-allyl- and alkenyl benzoic acid, etc.

3-(4-Methoxy-phen-yl)-1H-isochromen-1-one.

Abstract: The asymmetric unit of the title compound, C16H12O3, contains two crystallographically independent mol­ecules. The isochromene ring system is planar (maximum deviation 0.024 A) and is oriented at dihedral angles of 2.63 (3) and 0.79 (3)° with respect to the methoxy­benzene rings in the two independent mol­ecules.

1-(3-Phenyl-isoquinolin-1-yl)hydrazine.

Abstract: The title compound, C15H13N3, contains two independent mol­ecules in the asymmetric unit. The isoquinoline moiety and phenyl rings form dihedral angles of 4.38 (2) and 10.14 (3)° in the two independent mol­ecules. The crystal packing is stabilized by N—H⋯N mol­ecular dimers formed across a center of symmetry.

Repeatabilty of general and specific combining ability effects of seedling and clonal generations in potato

Abstract: The relative magnitude of general combining ability (gca) and specific combining ability (sca) effects in three generations (years), viz. Seedling (SG), first clonal generation (FCG) and second clonal generation (SCG) for tuber yield, tuber number, average tuber weight and tuber dry matter of potato in a line x tester mating design (10 x 4) was studied. There were marked differences in the gca effects of 14 parents. GCA and SCA for various characters varied from generation to generation. In general the correlation between various generations was varied and general conclusion could be arrived except in case of gca effects of males for dry matter. Considering the consistent performance over various generations for general combining ability, genotypes viz., MP/92–136, MP/91–65 and MP/90–95 for tuber yield and MP/92–136 for tuber number, Kufri Jyoti, for average tuber weight and MP/91–65 and QB/A-9-120 for dry matter were good general combiners, both in seedling and clonal generation. Similarly the crosses with consistent performance of specific combining ability over generations are cross MP/92–136 x Kufri Chipsona-1 for tuber yield and average tuber weight and QB/A-9-120 x MP/90–94 for tuber number and dry matter, were consistently good specific combiners in all generations. The variation in general combining ability effects over generation observed in the present study for tuber dry matter can be attributed to genotype x environment interaction. Hence, combining ability to select suitable parents for potato breeding has to be done based over years/generations. Parents and crosses with consistent performance over generations and those specifically suitable for breeding for processing quality were identified.

1-(3,5-Diethyl-1H-pyrazol-1-yl)-3-phenyl­isoquinoline

Abstract: In the title mol­ecule, C22H21N3, the isoquinoline ring is almost planar [maximum deviation = 0.046 (1) A] and makes dihedral angles of 52.01 (4) and 14.61 (4)° with the pyrazole and phenyl rings, respectively. The phenyl ring and the pyrazole ring are twisted by 44.20 (6)° with respect to each other. The terminal C atoms of both of the ethyl groups attached to the pyrazole ring are disordered over two sites with occupancy ratios of 0.164 (7):0.836 (7) and 0.447 (16):0.553 (16). A weak intra­molecular C—H⋯N contact may influence the mol­ecular conformation. The crystal structure is stabilized by C—H⋯π contacts involving the phenyl and pyrazole rings, and by π–π stacking inter­actions involving the pyridine and benzene rings [centroid–centroid distance = 3.5972 (10) A].

3-Phenyl-isoquinolin-1(2H)-one.

Abstract: The title compound, C15H11NO, consists of a planar isoquinolinone group to which a phenyl ring is attached in a twisted fashion [dihedral angle = 39.44 (4)°]. The crystal packing is dominated by inter­molecular N—H⋯O and C—H⋯O hydrogen bonds which define centrosymmetric dimeric entitities.

1-(4-Chloro-phen-yl)-2-phenyl-2-(3-phenyl-1-isoquinolylsulfan-yl)ethanone.

Abstract: The title compound, C29H20ClNOS, is a 1-substituted-3-phenyl­isoquinoline that crystallizes with four independent mol­ecules in the asymmtric unit. The four mol­ecules have similar C—S—C angles. The most noteworthy differences between the mol­ecules relate to the inclination of the 3-phenyl subsituent with respect to the isoquinoline fused-ring [dihedral angles of 21.2 (1), 25.6 (2), 34.3 (1) and 36.5 (2)°].

1-(4-Chlorophenyl)-2-[(3-phenylisoquinolin-1-yl)sulfanyl]ethanone

Abstract: The title compound, C23H16ClNOS, exhibits dihedral angles of 11.73 (1) and 66.07 (1)°, respectively, between the mean plane of the isoquinoline system and the attached phenyl ring, and between the isoquinoline system and the chloro­phenyl ring. The dihedral angle between the phenyl and chlorophenyl rings is 54.66 (1)°.

2,4-Dichloro-6-methoxy-quinoline.

Abstract: The title compound, C10H7Cl2NO, features a planar mol­ecule, excluding the methyl H atoms [maximum deviation = 0.0385 (1) A]. The crystal packing is stabilized by π–π stacking inter­actions across inversion centres [centroid-to-centroid distance = 3.736 (3) A].

2-[2-(Hydroxy-meth-yl)phen-yl]-1-phenyl-ethanol.

Abstract: The title compound, C15H16O2, has a dihedral angle of 1910 (5)° between the mean planes of the two benzene rings There is an intra­molecular O—H⋯O hydrogen bond and the C—C—C—C torsion angle across the bridge between the two rings is 17313 (14)° The mol­ecules form inter­molecular O—H⋯O hydrogen-bonded chains extending along the a axis C—H⋯π contacts are also observed between mol­ecules within the chains

2-[2-(Cyclo-hexyl-carbon-yl)phen-yl]-1-phenyl-ethanone.

Abstract: The title diketone, C21H22O2, features a phenyl­ene ring having benzoyl­methyl and cyclo­hexa­noyl substituents ortho to each other. The cyclo­hexyl ring adopts a chair conformation with the ketonic group occupying an equatorial position; the four-atom –C(O)–C ketonic unit is twisted out of the plane of the phenyl­ene ring by 34.9 (1)°.

Performance and stability of indigenous and exotic potato (Solanum tuberosum) cultivars for processing

Abstract: Field trials were conducted during 1998-2003 with 3 indigenous potato (Solanum tuberosum L.) processing cultivars, 'Kufri Chipsona 1', 'Kufri Chipsona 2' and 'Kufri Jyoti' and 2 exotic cultivars 'Atlantic' and 'FL 1533' at Agra, Indore, Jalandhar, Kufri, Modipuram and Ooty for wide adaptability. Observations on total and processing grade tuber yield, tuber dry matter (%) and chips colour were recorded. The genotype environment interaction was highly significant for all the characters. All the above 6 locations were suitable for production of quality potatoes for processing. Indigenously developed processing cultivars 'Kufri Chipsona 1' and 'Kufri Chipsona 2' were more stable for yield and processing traits. Their cultivation during summer in high hills (Ooty and Shimla), and in winter and spring seasons in north Indian plains (Indore, Agra, Modipuram and Jalandhar) could provide raw material to the processing industries for most part of the year. 'Kufri Chipsona 1' recorded the highest yield in most of the trials and had highly desirable processing attributes, i e high dry matter (>21%) and acceptable chip colour (<3.00).

1-(4-Chloro-3-fluoro­phen­yl)-2-[(3-phenyl­isoquinolin-1-yl)sulfan­yl]ethanone

Abstract: In the title compound, C23H15ClFNOS, the isoquinoline system and the 4-chloro-3-fluoro­phenyl ring are aligned at 80.4 (1)°. The dihedral angle between the isoquinoline system and the pendant (unsubstituted) phenyl ring is 19.91 (1)°.