Search results for "medicinal"

ChemInform Abstract: Polycondensed Nitrogen Heterocycles. Part 24. Pyrrolo(3,4-c) isoquinolinone by Thermal Rearrangement of a Pyrrolylbenzotriazinon…

2010

Rearrangement under acidic conditions of the pyrrolylbenzotriazinone 7 afforded the pyrrolylbenzamides 10 and 11. By thermal rearrangement instead, the first fully aromatic derivative of the pyrrolo[3,4-c]isoquinoline ring system 9 was obtained.

Abbau und Toxizität von Hexachlorbicyclo [2.2.1]-hept-5-en- Derivaten (Cyclodien-Insektizide) / Structural Aspects of Biological Conversion and Toxic…

1973

The aspects of molecular-structure and biological conversion have been studied for 12 derivatives of the endosulfan ether 1 [4, 5, 6, 7, 8, 8- hexachloro- 1, 3, 3a, 4, 7, 7a- hexahydro- 4, 7-methanoisobenzofuran]. Adults of a normal house-fly strain (Musca domestica) have been used in the assay. Derivatives of 1 monosubstituted in position I are found to be converted substantially faster than products disubstituted in position I and 3, respectively. Metabolism is inhibited for all compounds studied after application of piperonyl butoxide as a synergist. Besides proving that on oxidative metabolism has to be discussed and in fact could be proved for some derivatives, the intrinsic toxicity o…

(2S,5S)-2-(Bis(4-methoxyphenyl)((trimethylsilyl)oxy)methyl)-5-(4-methoxy-3,5-dimethylphenyl)pyrrolidine

2016

Harmful and Protective Effects of Terpenoids from African Medicinal Plants

2014

Terpenoids represent the most widespread group of natural products and can be found in all classes of living things. Many defensive compounds include sesquiterpenoids and diterpenoids from angiosperm species. Several terpenoids are biologically active and are exploited in the fight against cancer, malaria, inflammation, and a variety of infectious diseases. Nonetheless, some compounds of this group showed toxic effects causing gastrointestinal problems or central nervous system manifestations among others. Several bioactive terpenoids were identified in African medicine with numbers of them having organ-protective effects while few are known for their nonbeneficial properties for humans. In…

Metabolic Activation and Pharmacokinetics in Hazard Assessment of Halogenated Ethylenes

1981

Halogenated ethylenes play an important role in occupational and environmental medicine. Several attempts at toxicological evaluation of such compounds have been recently published (Maltoni 1977; Lee et al. 1978; Gehring et al. 1979; Kappus and Ottenwalder 1980; Henschler et al. 1980; Bolt 1980). The principal question is that of possible carcinogenicity. It is now clear that vinyl chloride (Maltoni 1977) and vinyl bromide (Bolt et al. 1979) are carcinogenic; some data also argue in favor of carcinogenicity of vinylidene chloride (Lee et al. 1978). Trichloroethylene (Henschler et al. 1980) and perchloroethylene (Bolt and Link 1980), according to present data, appear devoid of cancerogenic p…

ChemInform Abstract: Synthesis of the First Benzodiselenagermoles and One Spirobisdiselenagermole.

2010

Abstract The first examples of compounds R1R2GeSe2C6H4R3 (R1,R2=CH3 C2H5, C3H2, n-C4H9, i-C5H11, Ph, p-CH3Ph. R3=H, CH3, OCH3) were easily obtained (40–80% yield) from electrophilic cleavage of diselenophenylene zirconocenes by dialkyl or diaryl dichlorogermanes. The synthesis of a spirodi-selenagermole was achieved in the same way using germanium tetrachloride. Analytical data, 1H and 77Se NMR. mass spectra are perfectly consistent with the expected structures.

Uranium( iv ) cyclobutadienyl sandwich compounds: synthesis, structure and chemical bonding

2019

The 1 : 1 reactions of uranium(IV) tetrakis(borohydride) with the sodium and potassium salts of the cyclobutadienyl anion [C4(SiMe3)4]2− (Cb′′′′) produce the half-sandwich complexes [Na(12-crown-4)2][U(η4-Cb′′′′)(BH4)3] and [U(η4-Cb′′′′)(μ-BH4)3{K(THF)2}]2. In the 1 : 2 reaction of U(BH4)4 with Na2Cb′′′′, formation of [U(η4-Cb′′′′)(η3-C4H(SiMe3)3-κ-(CH2SiMe2)(BH4))]− reveals that a Cb′′′′ ligand undergoes an intramolecular deprotonation, resulting in an allyl/tuck-in bonding mode. A computational study reveals that the uranium–Cb′′′′ bonding has an appreciable covalent component with contributions from the uranium 5f and 6d orbitals. peerReviewed

Rhodium catalyzed oxidative coupling of salicylaldehydes with diazabicyclic olefins: a one pot strategy involving aldehyde C–H cleavage and π-allyl c…

2013

An efficient one pot strategy for the synthesis of cyclopentene fused chromanone derivatives through the direct oxidative coupling of salicylaldehydes with bicyclic olefins in the presence of a rhodium-copper catalyst system is described. This is the first report on the ring opening-ring closing of bicyclic hydrazines via metal catalyzed oxidative coupling reaction.

Phospholylmethano P-chirogenic-phosphine-borane as P-(η2-BH3)-chelating ligands of rhodium (I): Synthesis, characterization and asymmetric hydrogenat…

2021

International audience; The stereoselective synthesis of new phospholylmethano P-chirogenic-phosphine-borane was achieved by P-C bond formation of the bridge, using electrophilic or nucleophilic P*-building blocks. These P1CH2P2*.BH3 ligands behaved as chelating (κ1-P1)-(η2-BH3) entities towards the cationic rhodium(I) centre. The resulting chiral rhodium complexes were tested in asymmetric rhodium catalyzed hydrogenation of methyl 2-(acetamido)acrylate.

ChemInform Abstract: Boron Aldol Additions with Erythrulose Derivatives: Dependence of Stereoselectivity on the Type of Protecting Group.

2010

Abstract Boron aldol additions of 1- O -silylated 3,4-di- O -benzyl- and 3,4-di- O -benzoyl- l -erythrulose and achiral aldehydes using dicyclohexylboron chloride have been investigated. The dibenzyl derivative gave syn/syn stereoisomers with high stereoselectivity, whereas the dibenzoyl derivative gave syn/anti stereoisomers. It is believed that, while the dibenzoyl erythrulose gives rise to the E enolate in the presence of dicyclohexylboron chloride, as usually observed with this reagent, only the Z enolate is formed in the case of the dibenzyl derivative.