Guanidine–Guanidinium Cooperation in Bifunctional Artificial Phosphodiesterases Based on Diphenylmethane Spacers; gem-Dialkyl Effect on Catalytic Efficiency
摘要:
Diphenylmethane derivatives 1-3, decorated with two guanidine units, are effective catalysts of HPNP transesterification. Substitution of the methylene group of the parent diphenylmethane spacer with cyclohexylidene and adamantylidene moieties enhances catalytic efficency, with gem-dialkyl effect accelerations of 4.5 and 9.1, respectively. Activation parameters and DFT calculations of the rotational barriers around the C-Ar bonds indicate that a major contribution to the driving force for enhanced catalysis is entropic in nature.
Guanidine–Guanidinium Cooperation in Bifunctional Artificial Phosphodiesterases Based on Diphenylmethane Spacers; gem-Dialkyl Effect on Catalytic Efficiency
摘要:
Diphenylmethane derivatives 1-3, decorated with two guanidine units, are effective catalysts of HPNP transesterification. Substitution of the methylene group of the parent diphenylmethane spacer with cyclohexylidene and adamantylidene moieties enhances catalytic efficency, with gem-dialkyl effect accelerations of 4.5 and 9.1, respectively. Activation parameters and DFT calculations of the rotational barriers around the C-Ar bonds indicate that a major contribution to the driving force for enhanced catalysis is entropic in nature.
Dual-binding conjugates of diaromatic guanidines and porphyrins for recognition of G-quadruplexes
作者:Jagdeep Grover、Cristina Trujillo、Mona Saad、Ganapathi Emandi、Nikolina Stipaničev、Stefan S. R. Bernhard、Aurore Guédin、Jean-Louis Mergny、Mathias O. Senge、Isabel Rozas
DOI:10.1039/d0ob01264e
日期:——
The first conceptualised class of dual-binding guanine quadruplex binders has been designed, synthesised and biophysically studied.
第一个概念化的双结合鸟嘌呤四链体结合物类别已被设计、合成和生物物理学研究。
New aromatic iminoimidazolidine derivatives as α 1 -adrenoceptor antagonists: a novel synthetic approach and pharmacological activity
作者:Christophe Dardonville、Pilar Goya、Isabel Rozas、Angela Alsasua、Mª Isabel Martı́n、Mª José Borrego
DOI:10.1016/s0968-0896(00)00089-4
日期:2000.7
The design, synthesis and alpha(1)-adrenoceptor antagonism of a series of bis-imidazoline (1a, 2a, 3a and 4a) and bis-guanidine (1b, 2b, 3b and 4b) diphenyl derivatives are reported. All of these compounds fulfil the conditions of the most recent pharmacophore proposed for alpha(1)-adrenoceptors and found in the literature. Besides, a novel synthetic approach to the preparation of 2-(aryl-imino)imidazolidine derivatives is described. All the tested compounds, except the bis-guanidinium derivative 3b, inhibit the contractile responses induced by noradrenaline in aortic rings of rat and rabbit in a dose-dependent manner. Our results indicate that, even though some discrepancies are observed in terms of the alpha(1) subtype targeted by this new family of compounds, they show an interesting profile as antagonists of alpha(1)-adrenoceptors and a new prototype, compound 1a, has been found deserving further development. (C) 2000 Elsevier Science Ltd. All rights reserved.
Guanidine–Guanidinium Cooperation in Bifunctional Artificial Phosphodiesterases Based on Diphenylmethane Spacers; <i>gem</i>-Dialkyl Effect on Catalytic Efficiency
Diphenylmethane derivatives 1-3, decorated with two guanidine units, are effective catalysts of HPNP transesterification. Substitution of the methylene group of the parent diphenylmethane spacer with cyclohexylidene and adamantylidene moieties enhances catalytic efficency, with gem-dialkyl effect accelerations of 4.5 and 9.1, respectively. Activation parameters and DFT calculations of the rotational barriers around the C-Ar bonds indicate that a major contribution to the driving force for enhanced catalysis is entropic in nature.