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121.
α-氯代-4-氧代-4H-1-苯并吡喃-3-甲醛芳腙与N-取代苯基-马来酰亚胺在三乙胺作用下通过1,3-偶极环加成合成了一系列含3-(4-氧代-4H-1-苯并吡喃-3-基)-3a,6a-二氢-4,6-二氧代吡咯啉并[3,4-d]吡唑类衍生物. 化合物结构经元素分析, IR, 1H NMR及MS确证.  相似文献   
122.
The title compound, ethyl 5-amino-1-[(5'-methyl-1'-t-butyl-4'-pyrazolyl)carbonyl] -3-methylthio-1H-pyrazole-4-carboxylate 5, has been synthesized by the treatment of 4 with ethyl 2-cyano-3,3-dimethylthioacrylate, and its crystal structure was determined by X-ray diffraction method. The crystal belongs to monoclinic, space group P21/c with a = 12.194(4), b = 12.909(4), c = 11.607(4) (A), β= 90.183(5)°, V = 1827.2(10) (A)3, Mr = 365.45, Z = 4, Dc = 1.328 g/cm3, μ = 0.203 mm-1, F(000) = 776, R = 0.0586 and wR = 0.1558. Preliminary bioassays indicated that the title compound shows fungicidal and plant growth regulation activities.  相似文献   
123.
Six novel series of substituted thiazoline (V, VI, VII and VIII) and thiazolidinone derivatives (IX and X) resulting from 2,3-dihydro-1, 5-dimethyl-3-oxo-2-phenyl-1H-pyrazole-4-carbaldehyde (I) and 1-phenyl-3-p-tolyl-1H-pyrazolc-4-carbaldehyde (II) were synthesized. The course of this synthesis included the preparation of two new scries of disubstituted thiosemicarbazone precursors (III and IV) which were cyclized with phenacyl bromide, ethyl 2-chloroacetoacetate as well as ethyl bromoacetatc to afford the target thiazolines and thiazolidinoncs. The antipyretic activity of some representative compounds was performed.  相似文献   
124.
The crystal and molecular structure of 17-hydroxy-17 methylandrostano[3,2-c]pyrazole ethanoate (stanazolol ethanol solvate), C2H30N2OC2H5OH, has been determined by direct methods and refined by full-matrix least squares to a final R of 0.0577 for 4021 observed reflections and 245 parameters using Cu K radiation, = 1.54178 Å. The compound crystallizes in space group P212121 with Z = 4 molecules per unit cell. In the steroid skeleton the ring A adopts a half-chair conformation, being considerably strained, as a consequence of the fused planar pyrazole ring E. Rings B and C however are chairs and ring D has a 13,14 half-chair conformation. All rings of the steroid skeleton are trans-connected. The OH group of the solvated ethanol molecule is hydrogen bonded to the -oriented carbonyl substituent O(20) of ring D. The molecules are further held together in the crystal structure by head–tail hydrogen bonding between N(1)H in the pyrazole ring and O(20), which consequently is an acceptor for the two H-bonds. Overall the molecule lacks any significant curvature with no interplanar dihedral angle greater than 7°. Possible binding modes of stanazolol with the human androgen receptor are discussed.  相似文献   
125.
1 INTRODUCTION It is reported that diazo pyrazoles are im- portant intermediates in the synthesis of numerous fused pyrazole heterocyclic compounds, which maybe exhibit high pharmaceutical functions and pesticidal activity[1]. So far, diazotization is a…  相似文献   
126.
1INTRODUCTIONThiosemicarbazidespossessingNC=Sgroupareanessentialstructurefeatureresponsibleforvariousbiocidalproperties[1~7].Moreover,theyaretheconvenientandkeyintermediatesforthesyn-thesisofheterocycliccompoundssuchas1,3,4-thiadiazoles,1,2,4-triazoleand…  相似文献   
127.
1INTRODUCTIONManypyrazolederivativeshavebeenreportedtoshowvariousbiologicalactivitiestobeusedasbactericide[1],fungicide[2],herbicide[3],insecticide[4]andvirucide[5]agents.Inaddition,4-thiazolidinoneplaysavitalroleowingtoitswiderangeofbiologi-calactivities…  相似文献   
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