Copper(I) salt-mediated arylation of phosphinyl-stabilized carbanions and synthetic application to heterocyclic compounds
摘要:
The copper-mediated reaction of phosphinyl-stabilized carbanions 2a-c with aryl halides 1a-i in DMF or HMPA produced (arylmethyl)phosphonates 3-11 in good yields. Similar treatment of N-(2-iodophenyl)- and N-(2-iodophenyl)-N-methyl-alpha-(diethoxyphosphinyl)acetamides (12 and 14) led to 2-[(diethoxyphosphinyl)methyl]benzoxazole (13) and 1-methyl-3-(diethoxyphosphinyl)oxindole (15) in 71 and 85% yields, respectively. 4-(Ethoxycarbonyl)-3,4-dihydroisoquinoline N-oxide (33) was synthesized by the reaction of ethyl alpha-(o-formylphenyl)acrylate (31), derived from 6 and paraformaldehyde,with hydroxylamine. The cycloaddition of 33 to olefins such as dimethyl maleate, methyl acrylate, and styrene was studied.
Tandem Horner–Wadsworth–Emmons/Heck procedures for the preparation of 3-alkenyl-oxindoles: the synthesis of Semaxanib and GW441756
作者:Jana Lubkoll、Alessia Millemaggi、Alexis Perry、Richard J.K. Taylor
DOI:10.1016/j.tet.2010.03.018
日期:2010.8
developed to provide rapid access to 3-alkenyl-oxindoles from α-halo-anilides. This one-pot microwave accelerated process proceeds with catalytic palladium(II) acetate or tetrakis(triphenylphosphine)palladium, and has been used to prepare a range of adducts derivedfrom aromatic, heteroaromatic and aliphatic aldehydes. The procedures can be used to prepare N-unprotected oxindoles directly and the applicability
Explorations in Organic Chemistry Leading to the Total Synthesis of (±)-Gelsemine
作者:Fay W. Ng、Hong Lin、Samuel J. Danishefsky
DOI:10.1021/ja0204675
日期:2002.8.1
The totalsynthesis of (+/-)-gelsemine (1) is described. A defining phase of the effort involved recourse to a strategic oxetane ring (see compound 25). It was constructed anticipating an intramolecular displacement of the carbon (C17)-oxygen (O4) bond (see product 48). A key intermediate in the stereospecific elaboration of the oxetane linkage was enone 22, which was susceptible to two beta-face attacks
Indirubin, an active component in the traditional Chinese medicine formula Danggui Longhui Wan, shows promising anticancer effects. Meisoindigo is an analog derived from indirubin, which is less toxic and appears to be even more potent against cancer. In considering meisoindigo as a structural template for the development of new drugs, we designed and synthesized a series of 3-ylideneoxindole acetamides as novel anticancer agents. The acetamides were then evaluated for in vitro and in vivo anticancer activities. The 3-ylideneoxindole acetamides were found to have better anticancer activity than was indirubin-3'-oxime in several cancer cell lines and also displayed a spectrum of activity similar to that of the drug candidate roscovitine, a CDK inhibitor. Among the 3-ylideneoxindole acetamides, compound 10 showed particularly good efficacy. Cell cycle analysis further revealed that compound 10 arrested cells in the G1 phase and caused an increase in the sub-G1 population, indicating that the apoptosis pathway had been induced. In addition, exposure of cells to compound 10 led to the upregulation of the cell-cycle regulator cyclin D1, which was sustained at a high level. In contrast, the same compound induced a short-term elevation in the level of cyclin E, which was followed by a rapid decrease and the attenuation of Rb phosphorylation. Furthermore, a docking model suggests that compound 10 binds to the active site of CDK4. In testing the therapeutic potency of compound 10 on CT26-xenografted BALB/c mice, a significant reduction in tumor size comparable to that of cisplatin was found when administrated via the i.p. route. The mice presented no loss of body weight, indicating that this compound possesses low toxicity. In the future, we are planning in vivo investigations of these new active anticancer agents to better elucidate active mechanisms at the cellular level and thus benefit the development of anticancer therapies. (C) 2015 Elsevier Masson SAS. All rights reserved.
Minami Toru, Isonaka Takeshi, Okada Yoshiharu, Ichikawa Junji, J. Org. Chem, 58 (1993) N 25, S 7009-7015