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941.
942.
Oriol Porcar-Tost Bernat Pi-Boleda Jordi García-Anton Ona Illa Rosa M. Ortuño 《Tetrahedron》2018,74(51):7252-7260
Two new conjugates, hcptpyDP and hcptpyTP, of a terpyridine derivative incorporating artificial peptide moieties, have been synthesized and their use in the preparation of metal catalysts and organogelators has been investigated. Ru(II) complexes derived from these ligands showed electrochemical behavior and activity as catalysts in the epoxidation of olefins similar to that of Beller's catalyst. As organogelators, these conjugates were able to gelate a variety of solvents, from toluene to methanol, with satisfactory mgc (minimum gelation concentration) values. The presence of 4′-(4-carboxy)phenylterpyridine (hcptpy) moiety allows tuning the gelling properties and also influences the supramolecular self-assembling mode to produce chiral aggregates with respect to parent peptides DP and TP. In the case of the conjugates, π?π interactions provided by the aromatic moieties cooperate with inter-molecular hydrogen bonding between NH and CO in the amide groups. Further properties of peptide/terpyridine conjugates are under investigation in view of future applications. 相似文献
943.
944.
Mirosław Jabłoński 《Structural chemistry》2017,28(6):1697-1706
It is shown that the H ? B contacts in 1-silacyclohex-2-enes are clearly stabilizing and strong, whereas those in 1-silacyclopent-2-enes are much weaker. This result is supported by analysis of QTAIM-based parameters and appropriate structural changes taking place upon the open form → closed form transformation and is in full agreement with previous NMR spectroscopic data [Wrackmeyer et al. (2006) Appl Organometal Chem 20:99–105]. Also, the influence of electronic and steric effects originating from the presence of specific substituents on the strength of the H ? B contacts is discussed in detail. Some problems and ideas associated with the use of the so-called open-closed method utilized in assessing values of interaction energies are discussed in detail. Particular attention is paid to the correct choice of reference open systems. It is shown that their partial geometry optimization leads to reliable values of interaction energies. 相似文献
945.
946.
Wangdong Zeng Zhe Sun Tun Seng Herng Tho P. Gonalves Tullimilli Y. Gopalakrishna Kuo‐Wei Huang Jun Ding Jishan Wu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(30):8757-8761
The challenging synthesis of a laterally extended heptazethrene molecule, the super‐heptazethrene derivative SHZ‐CF3 , is reported. This molecule was prepared using a strategy involving a multiple selective intramolecular Friedel–Crafts alkylation followed by oxidative dehydrogenation. Compound SHZ‐CF3 exhibits an open‐shell singlet diradical ground state with a much larger diradical character compared with the heptazethrene derivatives. An intermediate dibenzo‐terrylene SHZ‐2H was also obtained during the synthesis. This study provides a new synthetic method to access large‐size quinoidal polycyclic hydrocarbons with unique physical properties. 相似文献
947.
Rafał Pierzchała 《Mathematische Annalen》2016,366(1-2):57-82
948.
949.
N. Buarque de Gusmáo M. Kaouadji F. Seigle-Murandi R. Steiman F. Thomasson 《光谱学快报》2013,46(8):1373-1380
Acrodontiolamide, a new fungal metabolite has been isolated from the cell-free culture medium of Acrodontium salmoneum. Its purification was achieved by centrifugal TLC on silica gel and the structural analysis was based on spectroscopic data relative to both the natural product and its diacetyl derivative. This secondary metabolite, identified with 3-(p-nitrophenyl)-3-hydroxy-4-dichloromethoxy-isobutanamide exhibited antifungal properties. 相似文献
950.
Triphenylamine derivatized phenylacetylene macrocycle with large two-photon absorption cross-section
Zhen Fang Marek SamocRichard D. Webster Anna SamocYee-Hing Lai 《Tetrahedron letters》2012,53(36):4885-4888
A phenylacetylene macrocycle (PAM) derivative containing triphenylamine as the framework was synthesized in one-step Sonogashira coupling. The photophysical and electrochemical properties were investigated in details. This hexamer shows significant enhancement in two-photon absorption cross-section relative to reported PAM derivatives. 相似文献