Stereoselective Oxidative Bioconjugation of Amino Acids and Oligopeptides to Aldehydes
作者:Henriette N. Tobiesen、Lars A. Leth、Marc V. Iversen、Line Næsborg、Søren Bertelsen、Karl Anker Jørgensen
DOI:10.1002/anie.202008513
日期:2020.10.12
stereoselective, near‐equimolar, and metal‐free oxidative bioconjugation of amino acids and oligopeptides to aldehydes is presented. Based on a newly developed organocatalytic oxidative concept, the C‐terminal and side‐chain carboxylicacid functionalities of amino acids and oligopeptides are shown to couple in a stereoselective manner to α‐branched aldehydes catalyzed by a chiral primary amine and a quinone as
GLYCOPEPTIDE AND LIPOGLYCOPEPTIDE ANTIBIOTICS WITH IMPROVED SOLUBILITY
申请人:Rafai Far Adel
公开号:US20120149632A1
公开(公告)日:2012-06-14
The invention relates to derivatives of glycopeptide and lipoglycopeptide antibiotics possessing an altered ionization state with respect to the parent glycopeptide or lipoglycopeptide antibiotic, and having the ability to be regenerated as the parent glycopeptide or lipoglycopeptide antibiotic under physiological conditions. These compounds are useful as antibiotics for the prevention and/or the treatment of bacterial infections.
SERIES OF HALOGENATED TETRACYCLIC TRITERPENE DERIVATIVES AND THEIR PREPARATION AND APPLICATION
申请人:SHANGHAI KING-X BIOTECH CO., LTD
公开号:US20220177511A1
公开(公告)日:2022-06-09
The invention provides a series of halogenated tetracyclic triterpene derivatives and their preparation and application. It is represented by the following general structural formula:
R
1
is halogen, R
2
is H, and the halogen is selected from fluorine, chlorine, bromine or iodine; or R
1
and R
2
are each fluorine, and R
3
is an amine, alcohol, amino acid, peptide or phosphate linked to oxygen through an acyl group.
The derivatives are relatively stable in rat whole blood through pharmacokinetic studies. The absolute bioavailability after a single intragastric administration for male and female rats was 15.6% and 28.4% respectively. The mean bioavailability was 22%. The derivatives showed better in vivo activities compared with the existing standard drugs enalapril and sacubitril valsartan sodium. Meanwhile, hydrophilic prodrugs of the tetracyclic triterpenoid derivatives in the present invention were prepared. The derivatives of the present invention can be used for preparing cardiovascular medicines.
Binding of a hemoregulatory tetrapeptide by a bis-guanidinium crown ether
作者:Andreas Späth、Burkhard König
DOI:10.1016/j.tet.2010.06.024
日期:2010.8
A synthetic receptor for the molecular recognition of a tetrapeptide in aqueous buffer was obtained by combining a luminescent crown ether with two pyrrole-guanidinium moieties. The compound interacts with ammonium carboxylates of complementary geometry and binds the hemoregulatory peptide Ac-Ser-Asp-Lys-Pro with K=7 x 10(3) M(-1) at physiological pH. Shorter fragments and other tetrapeptides show no or significant reduced affinity. The binding of the target peptide to the functionalized crown ether is signalled by an increase of its emission intensity. (c) 2010 Elsevier Ltd. All rights reserved.
Synthesis and biological evaluation of a novel 99mTc labeled 2-nitroimidazole derivative as a potential agent for imaging tumor hypoxia
Tumor hypoxia plays a major role in reducing the efficacy of therapeutic modalities like chemotherapy and radiation therapy in combating cancer. In order to target hypoxic tissues, a tripeptide ligand having a 2-nitroimidazole moiety, as a bioreductive species, was synthesized. The latter was radiolabeled with Tc-99m for imaging hypoxic regions of tumors and was characterized by means of its rhenium analogue. The biodistribution and scintigraphic image of the corresponding Tc-99m-complex showed accumulation in tumor and these results suggest that it could be a marker for imaging tumor hypoxia. Published by Elsevier Ltd.