18977-41-8Relevant articles and documents
Preparation of the key intermediate in the synthesis of GV143253A: The anti-MRSA/E injectable trinem
Maragni, Paolo,Mattioli, Mario,Pachera, Roberta,Perboni, Alcide,Tamburini, Bruno
, p. 597 - 605 (2002)
GV143253A is a broad-spectrum injectable β-lactam belonging to the class of trinem antibiotics. A key intermediate (3S,4R)-3-[(1R)-1-(tert-butyldimethyl- silyloxy)ethyl]-4-[-(6′R)-2′-[(E)-(pyrid-4yl)methylene]- 1′-oxocyclohex-6′-yl]azetidin-2-one (10) was identified and synthesized via different enolate coupling approaches, using enol ether, lithium, sodium, magnesium, tin, zinc, zirconium, and titanium enolates. Among these approaches, the synthesis of (3S,4R)-3-[(1R)-1-(tert-butyldimethylsilyloxy)ethyl]-4-[-(6′R)- 2′-[(E)-(pyrid-4yl)-methylene]-1′-oxocyclohex-6′-yl] azetidin-2-one (10) via a titanium enolate offered advantages in terms of greater diastereoselectivity, higher yield, robustness, and isolation of intermediates and was superior to the method previously used for preparing large quantities of drug substance for early development studies.
Synthesis and evaluation of the antiparasitic activity of bis-(arylmethylidene) cycloalkanones
Braga, Saulo F.P.,Alves, érika V.P.,Ferreira, Rafaela S.,Fradico, Jordana R.B.,Lage, Paula S.,Duarte, Mariana C.,Ribeiro, Tatiana G.,Júnior, Policarpo A.S.,Romanha, Alvaro J.,Tonini, Maiko L.,Steindel, Mário,Coelho, Eduardo F.,De Oliveira, Renata B.
, p. 282 - 289 (2014/01/06)
A series of bis-(arylmethylidene)-cycloalkanones was synthesized by cross-aldol condensation. The activity of the compounds was evaluated against amastigotes forms of Trypanosoma cruzi and promastigotes forms of Leishmania amazonensis. The cytotoxicity of the active compounds on uninfected fibroblasts or macrophages was established in vitro to evaluate the selectivity of their antiparasitic effects. Six compounds displayed trypanocidal activity against amastigotes intracellular forms of T. cruzi with IC50 values ranging from 7.0 to 249 μM. Besides these six compounds, eight other molecules exhibited significant leishmanicidal activity (IC50 values ranging from 0.6 to 110.4 μM). Two compounds can be considered as promising antiparasitic lead molecules because they showed IC50 values in the low-micromolar range (≤1.2 μM) with an adequate SI (≥19.9). To understand the mechanism of action of these compounds, two possible molecular targets were investigated: trypanothione reductase (TR) and cruzain.
Organometallic π-tweezers incorporating pyrazine- and pyridine-based bridging units
Al-Anber,Stein, Th.,Vatsadze,Lang
, p. 50 - 56 (2008/10/09)
The synthesis of heterobimetallic (TiCu, TiAg) and tetranuclear heterobimetallic (Ti2Ag2) transition metal complexes based on the organometallic π-tweezer building blocks [Ti](CCSiMe 3)2 is described. In [{[Ti](μ-σ,π-CCSiMe 3)2}M-LL]+ and [{[Ti](μ-σ,π- CCSiMe3)2}MLLM{(Me3SiCC-μ-σ,π) 2[Ti]}]2+ (M = Cu, Ag; LL = pyrazine- or pyridine-based bridging units) the metal containing parts are spanned by π-conjugated organic bridges LL. Depending on the nature of LL coordination polymers are also accessible. Pyrazine- and pyridine-based π-conjugated σ-donor molecules, such as 4,4′-bipyridine, 1,2-di(4-pyridyl)ethylene, 3,5-dipyridyl-1,2,4-triazole, N,N′-bis(4-pyridylmethylidene)benzene-1,4- diamine, 2,5-di(pyridylmethylidene)cyclopentanone, 2,6-di(4-pyridylmethylidene) cyclohexanone (LL, 2a-2g) can successfully be used to span heterobimetallic π-tweezer units of the type [{[Ti](μ-σ,π-CCSiMe3) 2}M]+ ([Ti] = (η5-C5H 4SiMe3)2Ti; M = Cu, Ag). The thus accessible di-cationic species [{[Ti](μ-σ,π-CCSiMe3) 2}MLLM{(Me3SiCC-μ-σ,π)2[Ti]}] 2+ (4), which are formed via the formation of [{[Ti](μ-σ, π-CCSiMe3)2}MLL]+ (3) complexes, can be isolated in yields between 66% and 99%. However, when C5H 4NCHCHC6H4CHCHNC5H4 (5a) and C5H4NCHNC6H4CHCHNC 5H4 (5b), respectively, are reacted with {[Ti](μ-σ,π-CCSiMe3)2}AgBF4(1c) in a 1:1 molar ratio, then the silver(I) ion is released from the organometallic π-tweezer 1c and coordination polymers [AgBF4 ? 5a] n (6a) and [AgBF4 ? 5b]n (6b) along with [Ti](CCSiMe3)2 (7) are formed in quantitative yield.
Bridged Cyanine Dyes. Part 3 . Zwitterionic Bis-4-pyridyl and Cationic Bis-dimethylanilino derivatives
Katritzky, Alan R.,Fan, Wei-Qiang,Jiao, Xue-Shun,Li, Qiao-Ling
, p. 1321 - 1325 (2007/10/02)
The preparation is described of two novel classes of bridged cyanines: zwitterionic bis-4-pyridyl and cationic bis-dimethylanilino and bis-methylcarbazolyl derivatives 5 and 11.In these compounds an uneven number of carbon atoms of the methine chain forms
