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Light‐Controlled Histone Deacetylase (HDAC) Inhibitors: Towards Photopharmacological Chemotherapy 下载免费PDF全文
Dr. Wiktor Szymanski Maria E. Ourailidou Dr. Willem A. Velema Prof. Dr. Frank J. Dekker Prof. Dr. Ben L. Feringa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16517-16524
Cancer treatment suffers from limitations that have a major impact on the patient’s quality of life and survival. In the case of chemotherapy, the systemic distribution of cytotoxic drugs reduces their efficacy and causes severe side effects due to nonselective toxicity. Photopharmacology allows a novel approach to address these problems because it employs external, local activation of chemotherapeutic agents by using light. The development of photoswitchable histone deacetylase (HDAC) inhibitors as potential antitumor agents is reported herein. Analogues of the clinically used chemotherapeutic agents vorinostat, panobinostat, and belinostat were designed with a photoswitchable azobenzene moiety incorporated into their structure. The most promising compound exhibits high inhibitory potency in the thermodynamically less stable cis form and a significantly lower activity for the trans form, both in terms of HDAC activity and proliferation of HeLa cells. This approach offers a clear prospect towards local photoactivation of HDAC inhibition to avoid severe side effects in chemotherapy. 相似文献
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The high-temperature (HT) phase of Y(BH(4))(3) has been prepared by heating of the as mechanochemically synthesised low-temperature (LT) phase of Y(BH(4))(3) to 194-216 °C and subsequent rapid cooling to ambient temperature. Although the differences in the crystal structure and vibrational spectra for these closely-related polymorphs are rather small, yet the NMR MAS (1)H and CP MAS (89)Y spectra reveal clear differences in the chemical shifts for both nuclei. The thermal decomposition process of both forms differs noticeably below 260 °C, decomposition being faster and more facile for the HT phase. The activation energy for thermal decomposition, calculated according to the Kissinger equation, is nearly three times lower for the HT than for the LT polymorph for the first step of the thermal decomposition signalling giant improvement of kinetics of H(2) desorption. 相似文献
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Wiktor Szymanski 《Tetrahedron》2008,64(14):3197-3203
An efficient, chemoenzymatic method for the multicomponent synthesis of unnatural tripeptides is presented. Development of a previously described procedure combines the diversity offered by multicomponent reactions with the selectivity of biocatalysts and allows the convenient introduction of varied amino acid moieties into the tripeptide scaffold, with control of the stereochemistry. Additionally, it allows the introduction of a methyl group to the amide nitrogen, leading to derivatives of N-methylated amino acids. 相似文献
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van Zijl AW Szymanski W López F Minnaard AJ Feringa BL 《The Journal of organic chemistry》2008,73(18):6994-7002
With a consecutive "asymmetric allylic alkylation (AAA)/cross-metathesis (CM)/conjugate addition (CA)" protocol it is possible to synthesize either stereoisomer of compounds containing a vicinal dialkyl array with excellent stereoselectivity. The versatility of this protocol in natural product synthesis is demonstrated in the preparation of the ant pheromones faranal and lasiol. 相似文献
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Agnieszka Wojciechowska Andrzej Kochel Wiktor Zierkiewicz 《Journal of Coordination Chemistry》2016,69(5):886-900
We synthesized a l-arginine containing Zn2+ complex and oxalate ions. {[Zn2(l-Arg)2(ox)2]·8H2O}n (1) (l-Arg =l-arginine, ox = oxalate) crystallize in the monoclinic space group P21 with a = 8.979(2), b = 9.840(2) (Å), c = 18.509(3) (Å), β = 95.58(3) (Å), V = 1627.6(6) Å3, and Z = 2. The zinc centers are six-coordinate via one l-arginine zwitterion and two bridging oxalates. The binuclear [Zn2(l-Arg)2(ox)2] units are linked via oxalate and form 1-D “stair-like” linear chains. The complex was characterized using FT-IR, FT-Raman, UV–vis spectroscopy, and thermal analysis techniques, as well as DFT methods. Electronic bands above 31,000 cm?1 originate in 1,3Au (n→π*) transitions within oxalate ions. Theoretical studies were performed for the model compound {[Zn(l-Arg)(Hox)2]·4H2O} using the fragment of the crystallographic structure of 1. The interaction energy (ΔE) values for l-arginine and two oxalate ions are comparable at -145 kcal mol?1. Natural bond orbital (NBO) analysis of the electronic structure and bonding is also discussed. 相似文献