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101.
Telekin is a eudesmane sesquiterpene-lactone naturally occurring in many medicinal plants with antitumour and anti-inflammatory activity. In this study, a series of 13-amino derivatives of telekin have been synthesised through Michael addition reaction, and their relative configurations were exemplified by the single crystal X-ray diffraction of the dimethylamine adduct. The in vitro cytotoxicity against three tumour cell lines of these amine derivatives was evaluated. The piperidine and 4-hydroxypiperidine adducts displayed stronger cytotoxic activity than telekin. 相似文献
102.
103.
Natalie L. Harvey Dr. Joanna Krysiak Dr. Supakarn Chamni Dr. Sung Wook Cho Prof. Dr. Stephan A. Sieber Prof. Dr. Daniel Romo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(4):1425-1428
An eleven‐step synthesis of (±)‐spongiolactone from 1,3‐cyclohexanedione is reported that relies on a diastereoselective, nucleophile‐catalyzed aldol lactonization (NCAL) process with an advanced ketoacid intermediate that installed the anticipated β‐lactone pharmacophore of the natural product. In addition, a stereoselective cyclohexenyl zinc addition to a substituted cyclohexanone simultaneously installed two fully substituted vicinal stereocenters. The reported synthesis enabled preliminary structure–activity studies that revealed a regio‐ and stereoisomeric derivative of spongiolactone with greater antiproliferative activity towards a leukemia (K562) cell line. Furthermore, unusual antiproliferative selectivity of these spongiolactone derivatives toward the K562 cell line was observed with no inhibition of the breast, liver, and lung cancer cell lines tested. 相似文献
104.
Dr. Yves‐Marie Legrand Dan Dumitrescu Dr. Arnaud Gilles Eddy Petit Dr. Arie van der Lee Dr. Mihail Barboiu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(15):4938-4941
Following earlier reports on the photochemical synthesis of 1,3‐dimethylcyclobutadiene 8 , 10 in a protective host matrix, theoretical calculations for the formation of that adduct have been recently performed by Rzepa. 13 The author formulated criticisms based mainly on density functional theory calculations of 1H NMR spectra. According to Rzepa the calculated spectra do not correspond with our measured spectra, which leads him to the conclusion that our interpretation is wrong, and that mainly cyclobutadiene has not been stabilized or even synthesized; we believe, however, that the initial model that Rzepa used for his calculations does not correspond to chemical reality or is at the very least a crude simplification of it, which implies that his calculations cannot match, in every point, our experimental spectra. Rzepa′s simplified models might be ‘reasonable’ from the theoretical point of view; however, in the case of assessment in the solid state, the theoretical setup does not force the system to preserve the confined stabilizing space defined by the crystalline matrix for encapsulated hosts in the solid state. Inversely, in the case of solution modeling, the theoretical setup is too rigid to properly assess the complex equilibria occurring in solution and to accurately determine the NMR spectra of exchanging species in solution. The inconsistency between our experimental results and the results of the theoretical models proposed by Rzepa is such that his conclusions are considered to be too far from experimental reality. Accurate modeling taking in account “reasonable” experimental details would be a worthwhile endeavor. 相似文献
105.
A new approach to 15-deoxy-Δ12,14-prostaglandin J2 and related structures based on the (±)-Corey lactone diol has been developed. The key stage of this approach involves building the structure of a prostaglandin (PG) derivative with leaving groups at positions 9, 13, and 15, followed by elimination of these groups by treatment with an organic base. 相似文献
106.
T. V. Kochikyan M. A. Samvelyan V. S. Harutyunyan A. A. Avetisyan 《Chemistry of Heterocyclic Compounds》2005,41(11):1362-1370
A method was developed for the production of 4-alkoxy-2-ethoxycarbonyl-2-ethoxycarbonylmethylbutanolides. The latter were
subjected to alkaline and acid hydrolysis, leading to 4-alkoxymethyl-2-carboxymethylbutanolides, from which lactone-containing
thioureas and amides of carboxylactones with novel structures were obtained.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1625–1633, November, 2005. 相似文献
107.
108.
α-取代内酯的立体选择硝基乙烯化反应研究 总被引:3,自引:2,他引:1
研究了α-取代内酯的立体选择硝基乙烯化反应.从金属离子对反应时间、温度及产率的影响实验中发现,Zn2+增加了反应活性.用1HNMR光谱确定了产物双键的立体构型,并初步探讨了反应历程. 相似文献
109.
Francesco Vinale Judyta Strakowska Pierluigi Mazzei Alessandro Piccolo Roberta Marra Nadia Lombardi 《Natural product research》2016,30(22):2575-2581
Trichoderma based products are considered an alternative to synthetic pesticides and fertilizers. These Trichoderma spp. are among the most studied and applied fungal BCAs in industry and agriculture and are known to secrete several secondary metabolites with different biological activities. The analysis of metabolic profiles (the ‘metabolome’) of Trichoderma species is complex because of the wide range of compounds produced and the molecular activities identified, including the recently determined role in the activation of plant resistance to biotic and abiotic stresses and growth promotion. A new 10-member lactone, but-2-enoic acid 7-acetoxy-6-hydroxy-2-methyl-10-oxo-5,6,7,8,9,10-hexahydro-2H-oxecin-5-yl ester, named cremenolide (1), has been isolated from culture filtrates of Trichoderma cremeum. The structure of cremenolide was determined by spectroscopic methods, including UV, MS, and 1D and 2D NMR analyses. In vitro tests showed that the purified compound inhibited the radial mycelium growth of Fusarium oxysporum, Botrytis cinerea and Rhizoctonia solani, and exerted a significant promotion of growth of tomato seedlings. 相似文献
110.
Masahiko Isaka Panida Chinthanom Sukitaya Veeranondha Sumalee Supothina J. Jennifer Luangsa-ard 《Tetrahedron》2008,64(49):11028-11033
Two novel cyclopropyl diketones, hamavellone A (1) and B (2), and two new 14-membered nonaketide macrolactones, hamigeromycin A (3) and B (4), together with six known compounds, 89-250904-F1 (radicicol analogue A, 5), pseurotin A (6), emodin (7), ω-hydroxyemodin (8), and emodin bianthrones (9 and 10) were isolated from the soil fungus Hamigera avellanea BCC 17816. The structures of the new compounds were defined by analysis of NMR and MS data. The absolute stereochemistry of 3 was addressed by chemical correlation to 5. Hamavellone B (2) exhibited antimalarial activity with an IC50 of 5.2 μg/mL, whereas it also showed comparable cytotoxicity. 相似文献