Condensed aromatics—XXIV. Cyclo[d.e.d.e.e.d.e.d.e.e]decakisbenzene

The macrocyclic condensed aromatic hydrocarbon C₄₀H₂₀ cyclo[d.e.d.e.e.d.e.d.e.e] decakisbenzene is treated. It belongs to the class of cycloarenes. The simple Hückel molecular orbital analysis has been performed and employed in the construction of a harmonic force field. The set of calculated vibrational frequencies is reported.     

Interaction of Dialkyl (α-Carbomethoxy-β,β,β-Trifluoro-Ethyl) and Dialkyl-S-Carboethoxychloromethylthiol Phosphates with Mammalian Esterases. Role of Esterases in Toxicity Mechanisms

Abstract

The interaction of insecticides (RO)₂P (0)OCH (CF₃) COOCK₃ (I) and (RO)₂P(0)SCH(X)COOC₂H₅ (X=Cl(II), Br(III); R=Me, Et, Pr, i-Pr, Bu, i-Bu, Am, Hex) with acetylcnolinesterase (ACnE), butyrylcholinesterase (BChE) and carboxylesterase (CE) was studied in connection with their role in organo-phosphate toxicity mechsnisms. Toxicity of I–III to mice was determined. I–III were not hydrolysed by CE and irreversibly inhibited all the enzymes, II, IIi had a greater inhibitory potency compared to I: lgk^II _AChE = 2–4 (I), 6 (II, III); lgk^II _BChE = 3–6 (I), 5–8 (II, III); lgk^II _CE = 3–7 (I), more than 8 (II, III). With multiple regression analysis the dependence of antienzymatic activity on hydrophobicity and steric properties of alkyl substituents was investigated. The contribution of the hydrophobic interactions to dChE and CE (enzymes-“sites of loss”) inhibition was the same and more significant than that to AChE (target enzyme) inhibition. Steric effects are more important in AChE inhibition. The dependences lg(I/LD₅₀) = f(ΓΠ) for I–III were in great extent determined by binding with nonspecific esterases that rises with increasing hydrophobicity. These results indicate that nonspecific esterases CE and BChE play a buffer role in toxic action of I and especially II and III.     

QSAR Studies on the Toxicity of Nitrobenzenes to Population Growth of Tetrahymena Pyriformis

IntroductionMost ofnitroaromatics are main environmentalpollutants.Those industrial chemicals have a highexposure to the aquatic ecosystems,especially inthe region of the Songhua River.Many quantitativestructure- activity relationships ( QSARs) havebeen developed to predict the toxicity of organicchemicals to environmentally important species[1] .QSARs have been developed for predicting thenitroaromatic compounds′ toxicity to aquaticspecies too[2— 5] . The most successful QSARs arethos…     

Condensed aromatics—XXIII. Cyclo[d.e.d.e.d.e.d.e.d.e.d.e]dodecakisbenzene (kekulene)

Some topological properties of coronoids are given. These systems have chemical counterparts in cycloarenes. For one of these molecules, viz. C₄₈H₂₄ kekulene, the simple Hückel molecular orbital analysis has been performed and employed in the construction of a harmonic force field. Finally the set of calculated vibrational frequencies is reported.     

QSAR Study of Nitrobenzenes’ Toxicity to Tetrahymena Pyriformis Using Semi-empirical Quantum Chemical Methods

1 INTRODUCTION Nitrobenzenes are an important class of industrial chemicals produced with substantial marketing volu-mes and a diverse range of use patterns[1].They are widely used as pesticides,solvents,explosives,dye-stuffs,etc.Most of the nitrobenzenes together with their derivatives are toxic,and they can cause dam-nification of human kidney,liver,eye,skin,blood system and so on[2～4].It is reported that all nitro-benzenes and their metabolites have mutagenicity,which induces the cyto…     

Prof. Dr. E. Gorter, 19. Februar 1881 –17. Februar 1954

Ohne Zusammenfassung     

Oral Anticancer Heterobimetallic PtIV−AuI Complexes Show High In Vivo Activity and Low Toxicity

Au^I-carbene and Pt^IV−Au^I-carbene prodrugs display low to sub-μM activity against several cancer cell lines and overcome cisplatin (cisPt) resistance. Linking a cisPt-derived Pt^IV(phenylbutyrate) complex to a Au^I-phenylimidazolylidene complex 2 , yielded the most potent prodrug. While in vivo tests against Lewis Lung Carcinoma showed that the prodrug Pt^IV(phenylbutyrate)-Au^I-carbene ( 7 ) and the 1 : 1 : 1 co-administration of cisPt: phenylbutyrate: 2 efficiently inhibited tumor growth (≈95 %), much better than 2 (75 %) or cisPt (84 %), 7 exhibited only 5 % body weight loss compared to 14 % for 2 , 20 % for cisPt and >30 % for the co-administration. 7 was much more efficient than 2 at inhibiting TrxR activity in the isolated enzyme, in cells and in the tumor, even though it was much less efficient than 2 at binding to selenocysteine peptides modeling the active site of TrxR. Organ distribution and laser-ablation (LA)-ICP-TOFMS imaging suggest that 7 arrives intact at the tumor and is activated there.     

Über die roten Anile. 1. Mitt.

Zusammenfassung Durch Anwendung der vonF. Kröhnke ¹ ausgearbeiteten Methode zur Darstellung von -Keto-carbonsäuren konnte man über die roten Anile VIII die entsprechenden -Keto-(3,4,5-trimethoxyphenyl)-alkancarbonsäuren (IX, XI) gewinnen. Die erfolgreich durchgeführte Synthese des -(p-Dimethylaminophenylimino)--keto--(3,4,5-trimethoxyphenyl)-valeriansäurenitrils (VIIIc) läßt auch die geplante Synthese von -(p-Dimethylaminophenylimino)--keto--[2,3,4,4-tetramethoxydiphenylyl-(6)]-valeriansäurenitril und der entsprechenden -Keto-säure (V, [H statt Br]) als hoffnungsvoll erscheinen.     

Correctionto Chin .J .Chem .2002,20,851— 857

Ａｆｔｅｒｏｕｒａｒｔｉｃｌｅｔｉｔｌｅｄ“Ｈｙｄｒｏｔｈｅｒｍａｌｓｙｎｔｈｅｓｅｓ ,ｓｕｐｒａｍｏｌｅｃｕｌａｒｓｔｒｕｃｔｕｒｅｓａｎｄｔｈｅｔｈｉｒｄ ｏｒｄｅｒｎｏｎ ｌｉｎｅａｒｏｐｔｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｔｈｒｅｅｃｏｐｐｅｒ(Ｉ)ｈａｌｉｄｅａｍｉｎｅｃｏｍ ｐｌｅｘｅｓｃｏｎｎｅｃｔｅｄｖｉａｓｅｃｏｎｄａｒｙｂｏｎｄｉｎｇｉｎｔｅｒａｃｔｉｏｎｓ”ｉｓｐｕｂｌｉｓｈｅｄｉｎＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＣｈｅｍｉｓｔｒｙ 2 0 0 2 ,2 0 ,85 1— 85 7,ａｎａｄｖｉｃｅｆｒｏ…     

Über die roten Anile. 2. Mitt.

Zusammenfassung Bei der Spaltung des -(p-Dimethylaminophenylimino)--keto--(3,4,5-trimethoxyphenyl)-valeriansäurenitrils (V) mit Chlorwasserstoffsäure entsteht die -Keto--(3,4,5-trimethoxyphenyl)-buttersäure (VII) und nicht, wie infolge des Versagens einiger typischen -Ketocarbonsäurereaktionen vermutet wurde, die 3-Hydroxy-4,5,6-trimethoxy-indan-3-carbonsäure.1. Mitt.:J. Michalský undL. Sadílek, Mh. Chem.90, 171 (1959).