Enantioselective synthesis of (R)-isocarvone from (S)-perillaldehyde

Synthesis and AChE inhibitory activity of new chiral tetrahydroacridine analogues from terpenic cyclanones

“…Regarding the synthesis of the terpenic chiral ketones used in this work (Table 1), the (S)-(À)-3-isopropenylcyclohexanone (12) was prepared from (S)-perillaldehyde (30) in approximately 45% yield by a synthetic route previously reported by our group (Scheme 2) [35]. The key strategic feature is the thiophenoxide opening of the a,b-epoxy ketones 31 with concomitant retro-aldol expulsion of acetone and subsequent desulfenylation of 32 by thiophenoxide to afford (S)-12.…”

“…As part of our studies directed towards the enantioselective synthesis of building blocks from terpenes [35,36], we describe herein the enantioselective synthesis of a new series of chiral tetrahydroacridine analogues 7 (Scheme 1).…”

A facile and single pot strategy for the synthesis of novel naphthyridine derivatives under microwave irradiation conditions using ZnCl2 as catalyst, evaluation of AChE inhibitory activity, and molecular modeling studies

“…In recent past, the ortho amino nitriles are used as important building blocks for the synthesis of tacrine analogues via Friedlander reaction mainly using AlCl 3 as catalyst (Marco et al, 2001;Marco et al, 2004;Barreiro et al, 2003;Leon et al, 2005). Similarly Lewis acids (Da Costa et al, 2009;Proctor and Harvey, 2000;Gamba et al, 2008) like InCl 3 , BF 3 ÁEt 2 O, FeCl 3 , BiCl 3 , SbCl 3 , SnCl 2 Á2H 2 O, RuCl 3 , CeCl 3 , NiCl 2 , CoCl 2 Á2H 2 O, and CsCl are also used as catalysts for the synthesis of tacrine analogues. Apart from tacrine analogues, more recently, chiral tetrahydroacridine analogues (Pisoni et al, 2010) was also reported as AchE inhibitors.…”

Adventures in Atropisomerism: Total Synthesis of a Complex Active Pharmaceutical Ingredient with Two Chirality Axes

“…Although several methods of preparing 7 were explored, including conversion of natural product ( R )-perillaldehyde to 7 , we pursued the asymmetric rhodium-catalyzed conjugate addition of isopropenylboronic acid pinacol ester 9 to cyclohexenone 8 for its direct, one-step access to cyclohexanone 7 (see Scheme ). A combination of 0.3 mol % of [Rh­(COD)­Cl] 2 with 0.66 mol % (S)-DTBM-SEGPHOS in a mixture of heptane, methyl alcohol (MeOH), and water delivered 7 in 89% yield and >99.5% enantiomeric excess (ee) .…”