Stereocontrolled epoxidations of cycloheptene derivatives in the palladium-catalyzed route to tropane alkaloids. Total syntheses of scopine and pseudoscopine
摘要:
Stereoselective total syntheses of the tropane alkaloids scopine (1) and pseudoscopine (3) have been developed via the chloroacetoxylation approach. Palladium-catalyzed 1,4-chloroacetoxylation of diene 6 afforded the key intermediate 7. Subsequent substitution of the allylic chloride by TsNH-with either retention (Pd(O) catalysis) or inversion (S(N)2) of configuration gave 10 and 16, respectively. The epoxy oxygen was introduced syn to the nitrogen function prior to cyclization by utilizing the syn-directive effect of the allylic sulfonamido group in the epoxidation. Cyclization of the epoxides 12 and 21, followed by replacement of the tosyl group by a methyl group and subsequent debenzylation, afforded the title compounds 1 and 3, respectively.
[EN] FLUOROPHENYL SUBSTITUTED MUSCARINIC RECEPTOR LIGANDS WITH SELECTIVITY FOR M3 OVER M2<br/>[FR] LIGANDS DES RÉCEPTEURS MUSCARINIQUES À SUBSTITUTION FLUOROPHÉNYLE AYANT UNE SÉLECTIVITÉ POUR M3 SUR M2
申请人:UNIV FRIEDRICH ALEXANDER ER
公开号:WO2019110521A1
公开(公告)日:2019-06-13
The present invention relates to fluorophenyl substituted muscarinic receptor ligands with selectivity for M3 over M2 and to the use of these compounds in the treatment of various diseases such as asthma, chronic obstructive pulmonary disease (COPD), bronchopulmonary dysplasia (BPD) and urinary incontinence.
Exo- and endo-6-hydroxy- and 6,7-epoxytropanes; Total synthesis of scopine, pseudoscopine, and nor-derivatives
作者:David E Justice、John R Malpass
DOI:10.1016/0040-4039(95)00836-2
日期:1995.6
Novel endo- 6,7-epoxy-8-azabicyclo[3.2.1]octanederivatives and the corresponding exo-analogues have been synthesized and show substantially different reactivity; the resistance of the exo-epoxides to ring opening during hydride reduction and catalytic hydrogenolysis is exploited in a total synthesis of scopine, pseudoscopine, and nor -derivatives.
Heusner; Zeile, Chemische Berichte, 1958, vol. 91, p. 2399,2403
作者:Heusner、Zeile
DOI:——
日期:——
Total synthesis of scopine, pseudoscopine, and nor- derivatives
作者:David E. Justice、John R. Malpass
DOI:10.1016/0040-4020(96)00693-x
日期:1996.9
Scopine and pseudoscopine have been synthesised from cyclohepta-3.5-dienol: the initial 1,4-fuctionalisation of the diene is based on a nitroso-cycloaddition. The use of the N-benzyloxycarbonyl group throughout the scheme allows ultimate reductive deprotection to yield N-methyl or novel NH (nor-) derivatives without damage to the exo-epoxide of the title compounds. Preliminary investigation of nitroso- cycloaddition to 5,6-epoxycyclohepta-1.3-diene is described. Copyright (C) 1996 Elsevier Science Ltd.
Polonovski; Polonovski, Bulletin de la Societe Chimique de France, 1928, vol. <4> 43, p. 83