Bacteriostats. VI. 1a Bacteriostatic Activities of Some Substituted Guanidines 1b

Rodríguez

et al. 2011

Arzneimittelforschung

Section: Decomposition Studysupporting

confidence: 73%

“…The band at 245 nm was originated from C=S chromophore [16]. This compound was identified as N,N'-difurfurylthiourea (5) as previously reported [17]. Compound 1o also appeared in a 10 % ratio.…”

Section: Decomposition Studysupporting

confidence: 66%

Study on the Decomposition Products of Thiadiazinthione and their Anticancer Properties

Rodríguez

et al. 2011

Arzneimittelforschung

“…Dichloromethane was dried with CaH 2 and stored over 3 Å molecular sieves. Preparation of thioureas was carried out by a reaction of selected amines and CS 2 by using a previously described general procedure 30 . N 1 , N 3 ‐dipropylcarbodiimide31 was prepared according to a slightly modified literature procedure32 (see below).…”

Section: Methodsmentioning

confidence: 99%

Basicity of Guanidines with Heteroalkyl Side Chains in Acetonitrile

et al. 2008

The pKa values of seven novel guanidine derivatives, six of them possessing heteroalkyl substituents capable of forming intramolecular hydrogen bonds, were determined in acetonitrile (MeCN) by using the UV/Vis spectrophotometric titration method. The obtained pKa values range from 24.7 to 27.2. The most basic among the studied guanidines was found to be by ca. 4 pKa units more basic than thewell‐known superbase N1,N1,N3,N3‐tetramethylguanidine (TMG). The trends in the changes in the measured pKa values were compared with the experimental (determined by the extended kinetic method) and theoretical [B3LYP/6‐311+G(2df,p)//B3LYP/6‐31G(d)] gas‐phase proton affinities. It was shown that basicity ordering of the bases with dimethylaminopropyl substituents in acetonitrile follows the trend encountered in the gas phase. However, this is not the case for the methoxypropyl‐substituted guanidines indicating that in these molecules formation of the intramolecular hydrogen bonds is to large extent hindered due to solvation by acetonitrile.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

“…General: Solvents and commercially available chemicals (supplied by Aldrich and Kemika) were purified by standard methods or used as purchased. The monosubstituted guanidines 2a – e were synthesized from thiourea and the corresponding amine from the monoalkylisothiouronium salt according to the literature procedure 15b,30. Deprotonation of the S ‐methylisothiouronium iodide salts was accomplished with potassium hydroxide and afforded neutral guanidines 2a – e in quantitative yield.…”

Section: Methodsmentioning

confidence: 99%

Triguanide Derivatives: Synthesis, Crystal Structure and Evaluation of the Proliferation Effect on Some Tumor Cell Lines

et al. 2012

One‐pot synthesis of new pentasubstituted triguanides 1a–e starting from the corresponding monosubstituted guanidine derivatives and diisopropylcarbodiimide is described and a mechanism for formation of the products observed is proposed. The structures of 1a–d were elucidated by spectroscopic analyses of their acetate salts. The structure of compound 1e was also confirmed by X‐ray crystallography using its sulfate salt. The X‐ray structure provided strong evidence of extensive electron delocalization within the triguanide core despite its non‐planar structure. In addition, the effect of tautomerism on the course of the reaction, with emphasis on possible reaction paths leading to the side products, is discussed in some detail. Finally, antiproliferative effects of the acetate salts of the newly prepared compounds on five cancer lines in vitro were evaluated. It was found that acetates of 1a–c exhibit strong cytostatic and cytotoxic activity, with the strongest effect observed for the acetate of benzyl derivative 1c.