Total Synthesis of (+)‐Clavolonine, (−)‐Deacetylfawcettiine, and (+)‐Acetylfawcettiine

New Lycopodium alkaloids from Lycopodium obscurum

“…The structures of known compounds, compared with literatures data, were identified as lycopodine, 13 anhydrolycodoline, 14 obscurinine, 9 obscurinine B, 8 lycoflexine, 15 acetyldihydrolycopodine, 16 (+)-acetylfawcettiine, 17 Ndemethyl-α-obscurine, 18 N-demethyl-β-obscurine. 19 Obscurumine C (1), colorless crystals, has a molecular formula C 16 indicated the connection of C-4/C-5/C-6.…”

Hypervalent iodine reagents in the total synthesis of natural products

“…Treatment of diols with excess DMP leads to the corresponding dicarbonylic derivatives, as reported in the synthesis of (+)-clavolonine (3 equiv DMP, CH 2 Cl 2 , rt, 2 h), 113 auripyrones A and B (4 equiv DMP, CH 2 Cl 2 , rt, 20 min), 126 echinopines A and B (4 equiv DMP, 16 equiv NaHCO 3 , CH 2 Cl 2 , 25 °C, 2 h), 152 and cylindrocyclophane A (5 equiv DMP, 10 equiv NaHCO 3 , CH 2 Cl 2 , 23 °C, 1 h). 207 However, the oxidation of substrates bearing two or more alcohol moieties can be performed chemoselectively.…”

“…77,78 The oxidation of a complex substrate bearing a primary alcohol has been described by Hirama and co-workers (Scheme 5). ROMPM, 114,115,118,183 ROBn, 80,90,104,106,110,124,191,192 ROTr, 180 ROMe, 94,101,107,113,192 RONPhth, 88 RON=CMe 2 , 88 ArOAllyl, 193 ArOMe, 108,130,131,192,194,195 ArOBn, 127,131 ArOTBS, 174 R 2 NBoc, 174,[194][195][196][197] 208 This IBX analogue generates only water during the oxidation, while DMP releases acetic acid. When DMP was applied the required keto ester was obtained in only 60%, with 40% of the starting lactone recovered (Scheme 6).…”

Lycopodium alkaloids from Palhinhaea cernua

“…[9][10] In our previous research on this plant, palhinine A, a novel C 16 N-type alkaloid was isolated. 9 We now report the isolation and structural elucidation of two new Lycopodium alkaloids (1-2) along with ten previously identified compounds (Figure 1), namely, lycoflexine N-oxide (3) 8 , lycoflexine (4), 11 lycodine (5), 12 α-obscurine (6), 12 dehydroisofawcettiine (7), 13,14 lycopodine (8), 14 5-acetyllycofoline (9), 15 acetylfawcettiine (10), 16,17 cernuine (11) 18 and lycocernuine (12). 18 …”