Chiral Synthons from the Iridoid Glucoside Antirrhinoside − Synthesis of a Carbocyclic Homonucleoside Analogue

Abstract

The synthetic modification of the natural cyclopentanoid monoterpene glucoside antirrhinoside is reported. Some stereoselective modifications have been performed on the bicyclic iridoidic ring, resulting in opening of the dihydropyran ring. A series of chiral synthons having a highly oxygenated

Centrifugal partition chromatography: an efficient tool to access highly polar and unstable synthetic compounds on a large scale

“…Elemental analysis of aucubin puried by chromatography: anal. calcd for C 15 H 22 O 9 $H 2 O: C,49.45;H,6.64;O,43.91. Found: C,49.35;H,6.78;O 44.11 ,49.45;H,6.64;O,43.91.…”

New HSV-1 Anti-Viral 1′-Homocarbocyclic Nucleoside Analogs with an Optically Active Substituted Bicyclo[2.2.1]Heptane Fragment as a Glycoside Moiety

“…In the series of 2′- or 3′-hydroxymetyl cyclopentane -1′-homocarbanucleosides, a few compounds presented a slight antiviral or anticancer activity [18,19], while 1′,3′-disubstituted cyclopentene analogs [20] or 2′,3′- cis diols [21], were found to be inactive. Other analogs synthesized had low or no antiviral activity [22,23,24], with the exception of the adenine analog [24]. However, a few chemical structures were fruitfully used to obtain active 1′-homocarbanucleosides (Figure 2), like for example: V , with a 2,2,3-trimethylcyclopentanol, active against HIV-1 and HIV-2 at an EC 50 = 4–14 µg/mL [25,26].…”

Toward the Total Synthesis of Ryanodol via Oxidative Alkyne–1,3-Diketone Annulation: Construction of a Ryanoid Tetracycle

“…6 This molecular transformation presumably begins by lactone hydrolysis followed by regioselective epoxide opening in a stereoelectronically favored 6-exo manner. While both electrophilic sites of the epoxide may participate in a 6-exo ring opening process, 18 two factors may play a significant role in controlling the regioselectivity for this reaction: (1) nucleophilic addition at C12 would result in a highly strained trans -fused bicyclo[3.3.0]octane motif, 19 and (2) the C11 position is activated by the neighboring alkene. 20 While those not familiar with previous studies to prepare ryanadol may be disappointed by the observation that both 17 and 18 are produced in this two-step process, the propensity for the bridging lactone to participate in translactonization chemistry between the C11 and C3 hydroxy groups is well understood.…”