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排序方式: 共有91条查询结果,搜索用时 15 毫秒
1.
以2-(3,4-环己基类二氧-5-异丙基)苯基乙醇(2)和3-异丙氧基-5,5-二甲基-1,3-环己烯酮(4)为原料,利用羰基α-位的烷基化反应和分子内的Friedel-Carfts反应为关键步骤,经9步反应,合成了多氧芳香型三环二萜类天然产物Salvinolone。 相似文献
2.
~~Pulse radiolysis of one-electron oxidation of rare tricyclic nucleoside derivative@赵红卫$Shanghai Institute of Nuclear Research, Chinese Academy of Sciences! Shanghai 201800,China
@江致勤$Department of Chemistry, Tongji Unviersity!Shanghai 200092,China
@窦大营$Shanghai Institute of Nuclear Research, Chinese Academy of Sciences! Shanghai 201800,China
@吴铁一$Shanghai Institute of Nuclear Research, Chinese Academy of Sciences! Shanghai 201800,China
@王文锋$Shanghai… 相似文献
3.
Ion Neda Carsten Melnicky Alexander Vollbrecht Axel Fischer Peter G. Jones Reinhard Schmutzler 《无机化学与普通化学杂志》1996,622(6):1047-1059
The reaction of methylisatoic acid anhydride 1 with benzylamines led to the N-benzyl-N′-methylanthranilamide derivatives 2 – 4 . Their reaction with phosphorus trichloride furnished the 2-chloro-1-halobenzyl/benzyl-3-methyl-4(1 H)-1,3,2-benzodiazaphosphorin-4-ones 5 – 7 which, upon reaction with bis-(2-chloroethyl)ammonium chloride/triethylamine, were converted into the P-bis-(2-chloroethyl)amino-1-halobenzyl/benzyl-3-methyl-4(1 H)-1,3,2-benzodiazaphosphorin-4-ones 8 – 10 and 12 . With 2-chloroethylammonium chloride/triethyl-amine the P? NHCH2CH2Cl-substituted compound 11 was obtained from the PIIICl-species 6 . The reaction of 8 – 10 and 12 with hexafluoroacetone (HFA) took an unusual course: apart from the oxidative addition of HFA and formation of the perfluoropinacolyl ring system, one of the two CH2CH2Cl groups was found to alkylate the CH3N atom with formation of a five-membered (diazaphospholane) ring in the tricyclic phosphoranes 13 – 16 . The reaction of 11 with HFA also produced a spirophosphorane 17 which involved a λ5-oxazaphosphetidine ring system. In the reaction of 8, 10 and 12 with tetrachloro-o-benzoquinone, an oxidative addition reaction with concomitant N-alkylation and formation of the tricyclic phosphoranes 18 – 20 was found to take place. Single crystal X-ray structure determinations are described for the phosphoranes 13, 14 and 16 , and for the precursor compound 9 . The following features are common to the isostructural compounds 13 and 16 and the diethyl ether hemisolvate of 14 : the (λ5)-spiro phosphorus atom lies out of the plane of the other atoms of the rings to which it is common, and the dioxaphospholane rings display a twist conformation. In the λ3P-compound 9 the phosphorus atom also lies out of the plane of the other ring atoms. 相似文献
4.
Mojca Dobnikar Marijan Kočevar Andrej Petrič Miha Tišler Bojan Verček 《Monatshefte für Chemie / Chemical Monthly》1989,120(3):269-272
Summary Syntheses of 1-methylimidazo[1,2-c]quinazolinium iodide (3) and 1-methylimidazo[2,1-f]pyrido[3,2-d]pyrimidinium iodide (4) are described. These tricyclic compounds react with nucleophiles derived from active methylene compounds to give the corresponding open-chain enamines.
Reaktionen von quaternisierten Imidazo-Chinazolinen und -Pyridopyrimidinen mit Verbindungen mit reaktiven Methylengruppen
Zusammenfassung Synthesen von 1-Methylimidazo[1,2-c]chinazoliniumjodid (3) und 1-Methylimidazo[2,1-f]pyrido[3,2-d]pyrimidiniumjodid (4) werden beschrieben. Diese tricyclischen Verbindungen reagieren mit einigen Carbanionen aus Verbindungen mit reaktiven Methylengruppen, wobei die offenkettigen Enamine entstehen.相似文献
5.
6.
T. A. Mastryukova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):65-68
Abstract The ability of the phosphoryl group to undergo enolization has been studied. The introduction of strongly electronegative substituents at thee α-carbon atom is shown to increase CH- acidity greately and result in the enolization of the P=O group. 相似文献
7.
A method of preparation of the title compound 1a avoiding the use of gaseous chlorine is described. Tetramethylthiuram disulfide 4 is oxidized with sulfuryl chloride to dime thyl thiocarbamoyl chloride 5, which is converted to 1a by means of phosphorus pentachloride. 相似文献
8.
The Diels–Alder reaction between 2,7‐cyclooctadienone and cyclopentadiene goes to completion to produce a bis adduct and mono adduct under InCl3 conditions. 2,6‐Cycloheptadienone undergoes sequential Diels–Alder reactions in the presence of AlCl3 with cyclohexadiene and cyclopentadiene to produce the bis adduct. The bis adducts were oxidatively cleaved to produce the [5.8.5] and [5.7.6] tricyclic systems. 相似文献
9.
Latif Kelebekli 《合成通讯》2013,43(22):2998-3009
Stereoselective synthesis of tricyclo[6.2.2.02,7]dodecane-3,6,9,10-tetrol was developed starting from p-benzoquinone. The endo selective Diels–Alder cycloaddition of p-benzoquinone and 1,3-cyclohexadiene afforded the corresponding bicyclic diketone. The synthesis of the title compound was based on the cycloadduct by selective reduction with NaBH4, acetylation with AcCl, and hydroxylation with OsO4-NMO. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource: Full experimental and spectral details.] 相似文献
10.
Battistina Asproni Gabriele Murineddu Paola Corona Grard A. Pinna 《Molecules (Basel, Switzerland)》2021,26(8)
Cannabinoids comprise different classes of compounds, which aroused interest in recent years because of their several pharmacological properties. Such properties include analgesic activity, bodyweight reduction, the antiemetic effect, the reduction of intraocular pressure and many others, which appear correlated to the affinity of cannabinoids towards CB1 and/or CB2 receptors. Within the search aiming to identify novel chemical scaffolds for cannabinoid receptor interaction, the CB1 antagonist/inverse agonist pyrazole-based derivative rimonabant has been modified, giving rise to several tricyclic pyrazole-based compounds, most of which endowed of high affinity and selectivity for CB1 or CB2 receptors. The aim of this review is to present the synthesis and summarize the SAR study of such tricyclic pyrazole-based compounds, evidencing, for some derivatives, their potential in the treatment of neuropathic pain, obesity or in the management of glaucoma. 相似文献