INTRAMOLECULAR CATIONIC [5 + 2] CYCLOADDITION REACTIONS PROMOTED BY TRIMETHYLSILYL TRIFLATE IN 3.0 M LITHIUM PERCHLORATE-ETHYL ACETATE: APPLICATION TO A FORMAL TOTAL SYNTHESIS OF (±)-ISOCOMENE
摘要:
Trimethylsilyl triflate is an effective reagent in 3.0 M lithium perchlorate-ethyl acetate for promoting intramolecular cationic [5 + 2] cycloaddition reactions. A formal total synthesis of the angular triquinane isocomene (10) is detailed. Cationic [5 + 2] cycloaddition of quinone monoketal 40 gives rise to tricyclic diketone 35 which is subsequently converted into the known tricyclic ketone 33. Addition of methyl lithium followed by acid-catalyzed rearrangement employing the Pirrung protocol affords (+/-)-isocomene (10). (C) 1997 Elsevier Science Ltd.
Pharmaceutical compounds, preparation, use and intermediates therefor
申请人:Burroughs Wellcome Co.
公开号:US04535183A1
公开(公告)日:1985-08-13
This invention is directed to novel ether compounds of formula (I) ##STR1## which are of value in medicine in the palliation of haemoglobinopathies, in particular sickle-cell anemia, and also in the palliation of pulmonary dyefunction, protection from the effects of hypoxia and the radio-sensitization of tumours. The invention is also directed to methods for the preparation of the ether compounds, to pharmaceutical formulations containing them, the preparation of such formulations and the use of the compounds in human medicine. Also provided by the invention are intermediates of value in the preparation of the ether compounds, by the methods described, and the preparation of the intermediates.
Iron-Catalyzed Intramolecular Perezone-Type [5 + 2] Cycloaddition: Access to Tricyclo[6.3.1.0<sup>1,6</sup>]dodecane
作者:Yongjiang Liu、Xiao Wang、Song Chen、Shaomin Fu、Bo Liu
DOI:10.1021/acs.orglett.8b00989
日期:2018.5.18
An iron-catalyzed perezone-type [5 + 2] cycloaddition toward tricyclo[6.3.1.01,6]dodecane scaffolds is presented, furnishing cycloadducts with two new C–C bonds and three to four stereogenic centers generated with typically good yields and excellent diastereoselectivities. Two independent conditions, catalytic FeCl3/PhCO3tBu (0.5 equiv/1 equiv) and stoichiometric FeCl3(2 equiv), have been respectively
A Total Synthesis of the Marine Alkaloid Ningalin B from (S)-Proline
作者:Katrin Hasse、Anthony C. Willis、Martin G. Banwell
DOI:10.1071/ch09158
日期:——
The title alkaloid 1 has been synthesized from (S)-proline (2) using a sequence of reactions involving oxidative bromination (of 2), N-alkylation, Suzuki–Miyaura cross-coupling, and bromination steps.
COMPOUNDS AND USES THEREOF FOR THE MODULATION OF HEMOGLOBIN
申请人:Global Blood Therapeutics, Inc.
公开号:US20170174654A1
公开(公告)日:2017-06-22
Provide herein are compounds and pharmaceutical compositions suitable as modulators of hemoglobin, methods and intermediates for their preparation, and methods for their use in treating disorders mediated by hemoglobin and disorders that would benefit from tissue and/or cellular oxygenation.
Compounds and uses thereof for the modulation of hemoglobin
申请人:Global Blood Therapeutics, Inc.
公开号:US10017491B2
公开(公告)日:2018-07-10
Provide herein are compounds and pharmaceutical compositions suitable as modulators of hemoglobin, methods and intermediates for their preparation, and methods for their use in treating disorders mediated by hemoglobin and disorders that would benefit from tissue and/or cellular oxygenation.