Combinatorial Synthesis through Disulfide Exchange: Discovery of Potent Psammaplin A Type Antibacterial Agents Active against Methicillin-ResistantStaphylococcus aureus (MRSA)
摘要:
Psammaplin A is a symmetrical bromotyrosine -derived disulfide natural product isolated from the Psammaplysilla sponge, which exhibits in vitro antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Inspired by the structure of this marine natural product, a combinatorial scrambling strategy for the construction of heterodimeric disulfide analogues was developed and applied to the construction of a 3828-membered library starting from 88 homodimeric disulfides. These psammaplin A analogues were screened directly against various gram positive bacterial strains leading to the discovery of a series of potent antibacterial agents active against methicillin-resistant Staphylococcus aureus (MRSA), Among the most active leads derived from these studies are compounds 104. 105, 113, 115, 123, and 128. The present, catalytically-induced. disulfide exchange strategy may be extendable to other types of building blocks bearing thiol groups facilitating the construction of diverse discovery-oriented combinatorial libraries.
Combinatorial Synthesis through Disulfide Exchange: Discovery of Potent Psammaplin A Type Antibacterial Agents Active against Methicillin-ResistantStaphylococcus aureus (MRSA)
摘要:
Psammaplin A is a symmetrical bromotyrosine -derived disulfide natural product isolated from the Psammaplysilla sponge, which exhibits in vitro antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Inspired by the structure of this marine natural product, a combinatorial scrambling strategy for the construction of heterodimeric disulfide analogues was developed and applied to the construction of a 3828-membered library starting from 88 homodimeric disulfides. These psammaplin A analogues were screened directly against various gram positive bacterial strains leading to the discovery of a series of potent antibacterial agents active against methicillin-resistant Staphylococcus aureus (MRSA), Among the most active leads derived from these studies are compounds 104. 105, 113, 115, 123, and 128. The present, catalytically-induced. disulfide exchange strategy may be extendable to other types of building blocks bearing thiol groups facilitating the construction of diverse discovery-oriented combinatorial libraries.
Carbonic Anhydrase XII Inhibitors Overcome Temozolomide Resistance in Glioblastoma
作者:Prashant Mujumdar、Joanna Kopecka、Silvia Bua、Claudiu T. Supuran、Chiara Riganti、Sally-Ann Poulsen
DOI:10.1021/acs.jmedchem.9b00282
日期:2019.4.25
C (1), when used in combination with clinically used chemotherapeutic drugs, including temozolomide, reverses multidrug resistance and increases survival in glioblastoma, a highly aggressive primary brain tumor. We showed previously that the mechanism of action of 1 is novel, acting to indirectly interfere with P-glycoprotein drug efflux activity as a consequence of carbonic anhydrase XII (CA XII) inhibition
Total synthesis of a dibromotyrosine alkaloid inhibitor of mycothiol S-conjugate amidase
作者:Andrew S. Kende、Jiong Lan、Junfa Fan
DOI:10.1016/j.tetlet.2003.10.117
日期:2004.1
sequences are described for the first totalsynthesis of a dibromotyrosine alkaloid (1) reported to inhibit a critical mycobacterial enzyme, mycothiol S-conjugate amidase. The O-benzyloxime of 4-hydroxyphenylpyruvic acid was dibrominated and successively linked to a 3-aminopropyl chain, then to a 4-aminobutylguanidine unit, followed by selective deprotections to yield alkaloid 1. In an improved variant, the
Defining the Mechanism of Action and Enzymatic Selectivity of Psammaplin A against Its Epigenetic Targets
作者:Matthias G. J. Baud、Thomas Leiser、Patricia Haus、Sharon Samlal、Ai Ching Wong、Robert J. Wood、Vanessa Petrucci、Mekala Gunaratnam、Siobhan M. Hughes、Lakjaya Buluwela、Fabrice Turlais、Stephen Neidle、Franz-Josef Meyer-Almes、Andrew J. P. White、Matthew J. Fuchter
DOI:10.1021/jm2016182
日期:2012.2.23
Psammaplin A (11c) is a marine metabolite previously reported to be a potent inhibitor of two classes of epigenetic enzymes: histone deacetylases and DNA methyltransferases. The design and synthesis of a focused library based on the psammaplin A core has been carried out to probe the molecular features of this molecule responsible for its activity. By direct in vitro assay of the free thiol generated upon reduction of the dimeric psammaplin scaffold, we have unambiguously demonstrated that 11c functions as a natural prodrug, with the reduced form being highly potent against HDAC1 in vitro (IC50 0.9 nM). Furthermore, we have shown it to have high isoform selectivity, being 360-fold selective for HDAC1 over HDAC6 and more than 1000-fold less potent against HDAC7 and HDAC8. SAR around our focused library revealed a number of features, most notably the oxime functionality to be important to this selectivity. Many of the compounds show significant cytotoxicity in A549, MCF7, and W138 cells, with the SAR of cytotcodcity correlating to HDAC inhibition. Furthermore, compound treatment causes upregulation of histone acetylation but little effect on tubulin acetylation. Finally, we have found no evidence for 11c functioning as a DNMT inhibitor.