Two New Aspidosperma Indole Alkaloids from Yunnan Kopsia arborea

Total Syntheses of <i>Lycopodium</i> and Monoterpenoid Indole Alkaloids Based on Biosynthesis-Inspired Strategies

“…Referring to Heathcock's work, 18) treatment of 34a with HBr in AcOH at room temperature (r.t.) gave the ammonium bromide salt, which was then basified with NaOH to give lycopodine (5) in 80% yield by pyrrolidine ring formation. Further, α-hydroxylation of the ketone in 5 gave flabelliformine (42) in 46% yield, thereby realizing the first asymmetric total synthesis of this alkaloid. 19) 1.3.…”

“…Starting from tetracyclic intermediate 34a, we completed the total syntheses of lycopodine (5) and flabelliformine (42), as follows (Chart 10). Referring to Heathcock's work, 18) treatment of 34a with HBr in AcOH at room temperature (r.t.) gave the ammonium bromide salt, which was then basified with NaOH to give lycopodine (5) in 80% yield by pyrrolidine ring formation.…”

“…Total Synthesis and Structure Elucidation of Kopsiyunnanine K The genus Kopsia, which belongs to Family Apocynaceae, is a rich source of monoterpenoid indole alkaloids possessing structural diversity as well as a wide range of biological activities. 37) As a result of our continuing chemical studies on novel bioactive alkaloids, we were able to accomplish the structure elucidation of several unique monoterpenoid indole alkaloids from Kopsia arborea native to Yunnan Province in China [38][39][40][41][42][43][44][45][46] (Chart 19).…”

Chemical Diversity and Bioactivities of Monoterpene Indole Alkaloids (MIAs) from Six Apocynaceae Genera

“…Kopsiyunnanines G ( 158 ) and kopsiyunnanines H ( 159 ) ( Figure 18 ) with an aspidosperma-containing skeleton were isolated from the aerial part of the Chinese Kopsia arborea [ 93 ]. Kopsihainins A ( 160 ), B ( 161 ), and C ( 162 ) were isolated as new compounds from K. hainanensis [ 89 ], along with the known compounds, kopsinine ( 163 ) [ 87 ] and methyl demethoxycarbonylchanofruticosinate ( 164 ) [ 94 ] were isolated from the stems of Chinese K. hainanensis .…”

“…Kopsiofficines H–L ( 269 – 273 ) [ 122 ] ( Figure 23 ), together with fourteen compounds, 164 , 208 , 239 , 241 , (+)- O -methyleburnamine ( 274 ) [ 93 ], (−)- O -methylisoeburnamine ( 275 ) [ 123 ], 16-isoeburnamine ( 276 ) [ 124 ], 20-oxoeburnamenine ( 277 ) [ 125 ], methyl 11, 12-methylenedioxychanofruticosinate ( 278 ) [ 99 ], methyl N-(decarbomethoxy)-11, 12-(methylenedioxy) chanofruticosinate ( 279 ) [ 126 ], O -methylleuconolamm ( 280 ) [ 127 ], leuconodine D ( 281 ) [ 128 ], oxayohimban-16-carboxylic acid ( 282 ) [ 129 ], and 19, 20-dihydroisositsirikine ( 283 ) [ 130 ] ( Figure 23 ), were identified from the stems of K. officinalis plant [ 122 ]. Compounds 164 , 241 , 270 , 271 , 274 , 275 , 279 , and 281 exhibited significant anti-inflammatory activity towards IL-1β, PGE2 and TNF-α at 5 μg/mL.…”