Crystal and Molecular Structures of 3-Carboxypropyltriphenylphosphonium Diiodobromide

Complexation in the 3-carboxypropyltriphenylphosphonium bromide–molecular iodine system in chloroform was studied. The maximum number of iodine molecules coordinated by 3-carboxypropyltriphenylphosphonium bromide was established by the spectrophotometric method using a function of the average-iodine number, and the stability constant of the complex was determined. The [(C₆H₅)₃P(CH₂)₃COOH]BrI₂ diiodobromide was studied by X-ray diffraction analysis. The characteristic feature of the crystalline salt was the formation of dimer associates: anionic associates were formed due to the Br···Br intermolecular interactions and cationic associates were formed due to the O···H–O hydrogen bonds. The data obtained were correlated to the results of quantum-chemical calculations.     

Synthesis and Structure of Tetraphenylphosphonium Carboxylates

Hydrates of tetraphenylphosphonium carboxylates were synthesized by the reaction of equimolar amounts of pentaphenylphosphorus with 2-methoxybenzoic, 2-nitrobenzoic, and maleic acids in benzene. The product of the pentaphenylphosphorus reaction with tetrafluorophthalic acid (mole ratio 2: 1) is bis- (tetraphenylphosphonium) tetrafluorophthalate hydrate. According to the X-ray analysis data, crystals of tetraphenylphosphonim carboxylates are formed by tetraphenylphosphonim tetrahedral cations and single- or double-charged carboxylate anions. Structural organization of the crystals is determined by C–H···O weak hydrogen bonds formed with the participation of carboxylate groups and water molecules or manifold C–H···F interactions between cations and anions.     

Synthesis and Properties of Onium Salts of Isocyanuric Acid. Crystal Structure of Tetraphenylphosphonium Isocyanurate

Previously unknown tetrabutylammonium and tetraphenylphosphonium isocyanurates were prepared, and their IR spectra were examined. The crystal structure of tetraphenylphosphonium isocyanurate was determined.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 3, 2005, pp. 417–421.Original Russian Text Copyright © 2005 by Flakina, Chekhlov, Kushch, Lyubovskaya.     

Crystal and Molecular Structure of OMPCTF

ＣｒｙｓｔａｌａｎｄＭｏｌｅｃｕｌａｒＳｔｒｕｃｔｕｒｅｏｆＯＭＰＣＴＦＷａｎｇＲｕｉ－Ｙａｏ；ＪｉｎＺｈｏｎｇ－Ｓｈｅｎｇ（ＬａｂｏｒａｔｏｒｙｏｆＲａｒｅＥａｒｔｈＣｈｅｍｉｓｔｒｙａｎｄＰｈｙｓｉｃｓ，ＣｈａｎｇｃｈｕｎＩｎｓｔｉｔｕｔｅｏｆＡ...     

Crystal and Molecular Structure of Quinide

ＣｒｙｓｔａｌａｎｄＭｏｌｅｃｕｌａｒＳｔｒｕｃｔｕｒｅｏｆＱｕｉｎｉｄｅＷＡＮＧＧａｎｇ－Ｌｉ；ＺＨＡＯＳｈｕ－Ｊｉｅ；ＣＨＥＮＤｅ－Ｃｈａｎｇ（ＮａｔｉｏｎａｌＩｎｓｔｉｔｕｔｅｆｏｒｔｈｅＣｏｎｔｒｏｌｏｆＰｈａｒｍａｃｅｕｔｉｃａｌａｎｄＢｉ...     

Molecular Structure of γ-Apienes. Crystal and Molecular Structure of Ferocin

The molecular structure of the sesquiterpene humulene ester ferocin isolated from plants of the Ferula genus was determined by x-ray structure analysis. The conformation of the 11-membered γ-humulene ring was analyzed by molecular mechanics. It was found that four energetically similar macrocycle conformations are characteristic of γ-apienes.__________Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 125–128, March–April, 2005.     

The Crystal and Molecular Structure of Fargesin

ＴｈｅＣｒｙｓｔａｌａｎｄＭｏｌｅｃｕｌａｒＳｔｒｕｃｔｕｒｅｏｆＦａｒｇｅｓｉｎＭａＹｕ－Ｌｉａｎｇ；ＨａｎＧｕｉ－Ｑｉｕ（ＮａｔｉｏｎａｌＬａｂｏｒａｔｏｒｙｏｆＮａｔｕｒａｌａｎｄＢｉｏｍｉｍｅｔｉｃＤｒｕｇｓ，ＢｅｉｊｉｎｇＭｅｄｉｃａｌＵｎ...     

Crystal and Molecular Structure of Cyanuric Acid

ＣｒｙｓｔａｌａｎｄＭｏｌｅｃｕｌａｒＳｔｒｕｃｔｕｒｅｏｆＣｙａｎｕｒｉｃＡｃｉｄＣｈｅｎＣｈａｎｇ－Ｚｈａｎｇ；ＳｈｉＪｉａｎ－ＱｉｕＬｉｎＺｈｏｕ－Ｂｉｎ；ＧａｏＤｏｎｇ－Ｓｈｏｕ；ＨｕａｎｇＸｉａｏ－Ｙｉｎｇ；ＬｉＤｉｎｇ（ＦｕｊｉａｎＩｎｓ...     

Molecular and Crystal Structure of Cinnam ylidene Acetophenone

１　ＩＮＴＲＯＤＵＣＴＩＯＮＣｕｒｒｅｎｔｌｙ，ｃｏｎｓｉｓｔｅｎｔｅｆｆｏｒｔｓｈａｖｅｂｅｅｎｍａｄｅｔｏｔｈｅｉｎｖｅｓｔｉｇａｔｉｏｎｏｆｏｒｇａｎｉｃｎｏｎｌｉｎｅａｒｏｐｔｉｃａｌ（ＮＬＯ）ｍａｔｅｒｉａｌｓ〔１〕．Ｓｏｍｅｏｆｃｉｎｎａｍｙｌｉｄｅｎｅａｃｅｔｏｐｈｅｎｏｎｅｄｅｒｉｖａｔｉｖｅｓｈａｖｅｆａｉｒｌｙｓｔｒｏｎｇｓｅｃｏｎｄｈａｒｍｏｎｉｃｇｅｎｅｒａｔｉｏｎ（ＳＨＧ）ａｎｄｔｈｅｒｅｆｏｒｅａｒｅｐｏｔｅｎｔｉａｌｕｓｅｆｕｌｉｎＮＬＯｆｉｅｌｄｓ．Ｄｕｒｉｎ…     

Crystal and Molecular Structure of Phosphoenolpyruvate Salts

Abstract

Phosphoenolpyruvate (PEP) plays central role in the storage and transfer of energy in biological systems. Its free energy of hydrolysis (-58.5 kJ mol^?1) is the highest known for monoesterified phosphate esters. Depending on pH PEP can occur as monoanion, dianion and trianion or as tri-basic acid. Studying PEP salts in different crystal forms provides additional information on its molecular flexibility, phosphate group conjugation with the enolpyruvate residue and kind of binding to different cations.     

Synthesis and Structure of Tetraphenylstibonium and Tetraphenylphosphonium Hydrogen Sulfates

Reactions of pentaphenylantimony and pentaphenylphosphorane with sulfuric acid yielded tetraphenylstibonium and tetraphenylphosphonium hydrogen sulfates, respectively; their crystal and molecular structure was determined.     

Molecular and Crystal Structure of Octamethyl-1,4-dioxacyclohexasilane

Using X-ray diffraction, we have observed flattening of the six-membered ring in the octamethyl-1,4-dioxacyclohexasilane molecules. According to the results of a quantum-chemical calculation [B3LYP/6-311+G(d)], this flattening is due to the low barrier to hindered internal rotation about the Si-O bonds.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 624–630, April, 2005.     

千解草甲素的晶体和分子结构

千解草(Pygmaeopremna Herbacea)为马鞭草科千解草属植物,分布在中国西南一带,尤以四川南部为多。民间用其茎叶治疗跌打损伤,风湿性关节炎,月经不调,产后瘀血,外感风寒、消化不良等病患,且疗效显著,广为应用。千解草属植物共有五种,均未见有关化学成份的报道。我们从千解草根的乙醚提取物中得到四种晶体,本文报道了具有代表性的千解草甲素的晶体和分子结构(1)。