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1.
B. H. Doreswamy Chandra K. Mantelingu M. A. Sridhar M. Mahendra 《Research on Chemical Intermediates》2014,40(8):2659-2665
The isolation of stable carbenes of the Arduengo and Wanzlick type has prompted us to look for stable nitrenium ions of the related structural type 1-Hydroxy-3-methyl benzotriazolium trifluromethane sulfonate. Nitrenium ions are azocations with structure and survive long enough under in vitro conditions to bind with biological nucleophiles, i.e. DNA bases, and play an important role in carcinogenic processes involving the metabolism of aromatic amines. The title compound (C15H16F3N6O5S) was isolated and crystallized in the monoclinic space group Cc with cell parameters a = 19.866(1) Å, b = 13.128(9) Å, c = 7.673(5) Å, and Z = 4. The structure has both intra- and intermolecular hydrogen bonds. 相似文献
2.
Trifluoroethanol is an efficient and recyclable medium in promoting one-pot, three-component condensation reactions of β-ketoesters, aldehydes, and urea (or thiourea) to afford the corresponding dihydropyrimidones in good yields. This protocol does not require the use of an acid or base catalyst. 相似文献
3.
Chigalli N. Revanna Goravanahalli M. Raghavendra Kebbahalli N. Nandeesh Doddamedur G. Bhadregowda Kanchugarakoppal S. Rangappa Kempegowda Mantelingu 《Tetrahedron letters》2013
5-Allyl-7,7-difluoro-2-(2,4-difluorophenyl)-6-(4-methoxyphenyl)-4,5,6,7-tetrahydro-2H-pyrazolo[4,3-c]pyridine-3-amine represents a fluorinated heterocyclic scaffold, potentially attractive. It was synthesized via Michael addition, Mannich reaction of the difluorinated ethyl bromoacetate with a benzotriazole derivative, followed by a Dieckmann condensation. Starting from simple materials, this efficient route which gives access to novel functionalized N-(5-allyl-7,7-dihalo)-4,5,6,7-tetrahydro-2H-indazol-3-yl)-carboxymides, was explored and adapted for parallel synthesis, resulting in a compound library. 相似文献
4.
The kinetics of oxidation of L ‐amino acids (AAs) glycine( 1a ), alanine( 1b ), valine( 1c ), isoleucine( 1d ), leucine( 1e ), proline( 1f ), and phenylalanine( 1g ) by a transition metal ion (Mn3+) was studied in the presence of sulfuric acid medium at 26°C by a spectrophotometrical (λmax = 500 nm) method. In all cases, the kinetics of reactions was of first‐order with respect to each [AA] and [Mn3+]. Increased [H+], [Mn2+] (the reduction product of Mn3+), sulfate, and chloride had no effect on the reaction rate. However, the reaction rate increased with increased dielectric constant of the medium. Oxidation rate increased for 1a–g and an apparent correlation was observed between the rate of oxidation and nucleophilicty of AAs except for 1a and 1g . The reaction rate also linearly depended on the hydrophobicity of AAs except for 1f and 1g . The thermodynamic parameters for AA‐metal ion complex formation and activation parameters for the rate‐limiting steps have been evaluated. Analysis of the oxidation products indicated that the AAs underwent oxidative deamination and decarboxylation to form corresponding aldehydes. Based on these data, plausible mechanisms involved in the oxidation of AAs are proposed. © 2011 Wiley Periodicals, Inc. Int J Chem Kinet 43: 599–607, 2011 相似文献
5.
C.?V.?Kavitha S.?Lakshmi Basappa K.?Mantelingu M.?A.?Sridhar J.?Shashidhara?Prasad K.?S.?RangappaEmail author 《Journal of chemical crystallography》2005,35(12):957-963
1-(cyano-(4-methoxyphenyl) methyl cyclohexanol(2), C24H32N2O2, a Venlafaxine intermediate is found to crystallize in both monoclinic(2a) and orthorhombic(2b) crystal systems. The form2a crystallizes in the space groupC2/c with the cell parametersa = 23.506(3),b = 5.550(3),c = 23.192(3), and β = 115.116(2)^∘.2b crystallizes in space groupP212121 with cell parametersa = 5.7850(6),b = 11.2680(6), andc = 20.6730(19). The intermolecular hydrogen bonding in the case of the monoclinic polymorph leads to the formation of dimer.
The synthesis, characterization, and crystal structure studies of Venlafaxine analog 1-[2-1-(4-dimethylamino-phenyl)-ethylideneamino]-1-(4-methoxy-phenyl)-ethyl]-cyclohexanol(4) is reported.4 crystallizes inP―1 space group with cell parametersa = 10.801(7),b = 12.078(7),c = 9.928(5), α = 96.12(5)^∘, β = 110.49(5)^∘, and γ = 112.42(6)^∘. 相似文献
6.
T.A. Jenifer Vijay Kebbahalli N. NandeeshGoravanahalli M. Raghavendra Kanchugarakoppal S. RangappaKempegowda Mantelingu 《Tetrahedron letters》2013
A convenient one-pot method for the synthesis of thiochromen-4-ones by the condensation of 2′-haloacetophenone and dithioesters at room temperature in the presence of NaH in DMF in moderate to good yields has been developed. The method involves unusual intramolecular S-arylation. The reaction is operationally facile, readily scalable and offers rapid entry into substituted chromene-4-ones. 相似文献
7.
H. Mallesha K. R. Ravi Kumar B. K. Vishu Kumar K. Mantelingu K. S. Rangappa 《Journal of Chemical Sciences》2001,113(4):291-296
α, N-diarylnitrones were synthesized by the reduction of a mixture of nitro-and benzaldehyde derivatives with zinc dust using
histidine as a catalyst. 相似文献
8.
A new type of covalent binderless bulk modified electrode has been fabricated and used in the simultaneous determination of lead and cadmium ions at nanomolar level. The modification of graphitic carbon with 4-amino salicylic acid was carried out under microwave irradiation through the amide bond formation. The electrochemical behavior of the fabricated electrode has been carried out to decipher the interacting ability of the functional moieties present on the modifier molecules toward the simultaneous determination of Pb2+ and Cd2+ ions using cyclic and differential pulse anodic stripping voltammetry. The possible mode of interaction of functional groups with metal ions is proposed based on the pKa values of the modifier functionalities present on the surface of graphitic carbon particles. The analytical utility of the proposed sensor has been validated by measuring the lead and cadmium content from pretreated waste water samples of lead acid batteries. 相似文献
9.
Mantelingu K Kishore AH Balasubramanyam K Kumar GV Altaf M Swamy SN Selvi R Das C Narayana C Rangappa KS Kundu TK 《The journal of physical chemistry. B》2007,111(17):4527-4534
Reversible acetylation of nucleosomal histones and nonhistone proteins play pivotal roles in the regulation of all the DNA templated phenomenon. Dysfunction of the enzymes involved in the acetylation/deacetylation leads to several diseases. Therefore, these enzymes are the targets for new generation therapeutics. Here, we report the synthesis of trifluoromethyl phenyl benzamides and their effect on histone acetyltransferase (HAT) activity of p300. One of these benzamides, CTPB (N-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxy-6-pentadecyl-benzamide), was discovered as a potent activator of the p300 HAT activity. We have found that pentadecyl hydrocarbon chain of CTPB is required to activate the HAT only under certain context. Furthermore, our results show that the relative position of -CF3 and -Cl in CTB (N-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxy-benzamide) is also very critical for the activation. Surface-enhanced Raman spectroscopy (SERS) of p300 and the HAT activator complexes evidently suggest that the activation of HAT activity is achieved by the alteration of p300 structure. Therefore, apart from elucidating the chemical basis for small molecule mediated activation of p300, this report also describes, for the first time, Raman spectroscopic analysis of the complexes of histone-modifying enzymes and their modulators, which may be highly useful for therapeutic applications. 相似文献
10.
Goravanahalli M. Raghavendra Chottanahalli S. Pavan Kumar Gejjalagere P. Suresha Kanchugarakoppal S. Rangappa Kempegowda Mantelingu 《中国化学快报》2015,26(8):963-968
An efficient methodology for the synthesis of 2,3-disubstituted 3H-quinazolin-4-ones is described via one-pot three component reaction from anthranilic acid using T3P as catalyst. Mild reaction conditions, short reaction time, broad functional group tolerance, easy isolation of products and good yields are main advantages of this protocol. 相似文献