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21.
Vasu Govardhana Reddy P Suresh Reddy C Naga Raju C 《Chemical & pharmaceutical bulletin》2003,51(7):860-863
N-(substituted)-N'-(2,3-dihydro-5-benzoyl-2-oxido-1H-1,3,2-benzodiazaphosphol-2-yl) ureas were synthesized by reacting 3,4-diaminobenzophenone (4) with different chlorides of carbamidophosphoric acids (3) in the presence of triethylamine at 40-45 degrees C. Their 1H-, 13C- and 31P-NMR spectral data are discussed. The title compounds were screened for antifungal and antibacterial activity against the fungi Aspergillus niger and Fusarium solani and bacteria Escherichia coli and Staphylococcus aureus. These compounds showed higher antibacterial activity when compared with antifungal activity. 相似文献
22.
A series of new complexes, Mo(2)O(2)S(2)[S(2)P(OR)(2)](2) (where R = Et, n-Pr, i-Pr) and Mo(2)O(2)S(2)[S(2)POGO](2) (where G = -CH(2)CMe(2)CH(2)-, -CMe(2)CMe(2)-) have been prepared by the dropwise addition of an ethanolic solution of the ammonium or sodium salt of the appropriate O,O-dialkyl or -alkylene dithiophosphoric acid, or the acid itself, to a hot aqueous solution of molybdenum(V) pentachloride. The complexes were also formed by heating solutions of Mo(2)O(3)[S(2)P(OR)(2)](4) or Mo(2)O(3)[S(2)POGO](4) species in glacial acetic acid. The Mo(2)O(2)S(2)[S(2)P(OR)(2)](2) and Mo(2)O(2)S(2)[S(2)POGO](2) compounds were characterized by elemental analyses, (1)H, (13)C, and (31)P NMR, and infrared and Raman spectroscopy, as were the 1:2 adducts formed on reaction with pyridine. The crystal structures of Mo(2)O(2)S(2)[S(2)P(OEt(2))](2), Mo(2)O(2)S(2)[S(2)P(OEt)(2)](2).2NC(5)H(5), and Mo(2)O(3)[S(2)P(OPh)(2)](4) were determined. Mo(2)O(2)S(2)[S(2)P(OEt)(2)](2) (1) crystallizes in space group C2/c, No. 15, with cell parameters a = 15.644(3) ?, b = 8.339(2) ?, c = 18.269(4) ?, beta = 103.70(2) degrees, V = 2315.4(8) ?(3), Z = 4, R = 0.0439, and R(w) = 0.0353. Mo(2)O(2)S(2)[S(2)P(OEt)(2)](2).2NC(5)H(5) (6) crystallizes in space group P&onemacr;, No. 2, with the cell parameters a = 12.663(4) ?,b = 14.291(5) ?, c = 9.349(3) ?, alpha = 100.04(3) degrees, beta = 100.67(3) degrees, gamma = 73.03(3) degrees V = 1557(1) ?(3), Z = 2, R = 0.0593, and R(w) = 0.0535. Mo(2)O(3)[S(2)P(OPh)(2)](4) (8) crystallizes in space group P2(1)/n, No. 14, with cell parameters a = 15.206(2)?, b = 10.655(3)?, c = 19.406(3)?, beta = 111.67(1) degrees, V = 2921(1)?(3), Z = 2, R = 0.0518, R(w) = 0.0425. The immediate environment about the molybdenum atoms in 1 is essentially square pyramidal if the Mo-Mo interaction is ignored. The vacant positions in the square pyramids are occupied by two pyridine molecules in 6, resulting in an octahedral environment with very long Mo-N bonds. The terminal oxygen atoms in both 1 and 6 are in the syn conformation. In 8, which also has a distorted octahedral environment about molybdenum, two of the dithiophosphate groups are bidentate as in 1 and 6, but the two others have one normal Mo-S bond and one unusually long Mo-S bond. 相似文献
23.
Raju Ranjith Kumar 《Tetrahedron》2007,63(33):7850-7857
A series of new 2-methyl-11-aryl-4-[(E)-arylmethylidene]-1,2,3,4,11,11a-hexahydropyrido[3,4-c][1,5]benzothiazepines were obtained by the reaction of o-aminothiophenol and (E)-1-methyl-3,5-bis(arylidene)-4-piperidones in the presence of a catalytic amount of acetic acid under solvent-free microwave irradiation. These dipolarophiles undergo a highly atom economic 1,3-dipolar cycloaddition with nitrile oxide to afford a series of novel 6-methyl-1-phenyl-8-aryl-4-[(E)-arylmethylidene]-4,5,6,7,7a,8-hexahydro[1,2,4]oxadiazolo[5,4-d]pyrido[3,4-c][1,5]benzothiazepines stereoselectively. 相似文献
24.
Raju Thundathil James O. Stoffer Stig E. Friberg 《Journal of polymer science. Part A, Polymer chemistry》1980,18(8):2629-2640
Polymerization was made at 60°C in a lyotropic liquid crystal of sodium undecenoate and water. The liquid crystalline structure prior to polymerization was identified by optical microscopy and low-angle x-ray diffraction as an array of hexagonal closely packed cylinders with the hydrophobic part of the soap in the center of the cylinders. During polymerization the structure became isotropic at 60°C. Cooling to 20°C transformed the structure to a lamellar liquid crystal–a reversible transition. The structure of the lamellar phase was interpreted as a polyethylene backbone from which deformed decanoate chains reached toward the aqueous layer. Molecular models showed the model to accept head-tail, head-head, and tail-tail configurations in cis and trans conformations with the exception of the cis tail-tail configuration. 相似文献
25.
L. H. Johnston S. R. Raju G. R. Sudhakaran R. M. Lees 《International Journal of Infrared and Millimeter Waves》1982,3(4):517-527
Laser-Stark spectra have been observed for methyl alcohol using the 311 m line of the HCN laser. Partial assignments are presented for the three most distinctive structures in the spectra. The low field structure is clearly associated with a member of the J=2019qRa-type multiplet, and is tentatively identified as the k=13 A vt=0 transition. The other two structures originate from the 9382 E vt=0 transition, and from a member of the k= 65 A vt=1 Q branch, tentatively assigned as the J=32 member. 相似文献
26.
K. Rosi ReddyCh. Venkateshwar Reddy M. MaheshP.V.K. Raju V.V. Narayana Reddy 《Tetrahedron letters》2003,44(44):8173-8175
N-Butyl-N,N-dimethyl-α-phenylethylammonium bromide catalyzes efficiently the three component condensation reaction of an aromatic aldehyde, a β-keto ester and urea/thiourea under solvent free conditions at 100°C to afford the corresponding dihydropyrimidinone in high yield. 相似文献
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Murthy I. S. Sreenivasulu R. Alluraiah G. Ramesh Raju R. 《Russian Journal of General Chemistry》2019,89(8):1718-1723
Russian Journal of General Chemistry - A series of novel 1,2-isoxazole-pyridobenzimidazole is synthesized. Structures of the products are supported by 1H and 13C NMR, and mass spectra. All... 相似文献