The transformation of phyllocladene into a neoatisirane system

Ruthenium-Catalyzed Rearrangement of ent-14-(Benzoyloxy)-15,16-epoxybeyerane Diterpenes

“…3 Hz, H-16), 2.03 (3H, s, MeCOO), 1.04, 0.99, 0.83 (3H each, s); 13 Hz, H-15), 4.47 (1H, br s, H-14), 3.82 (1H, Q AB , J ) 10.9 Hz, H-18), 3.64 (1H, Q AB , J ) 10.9 Hz, H-18), 2.47 (1H, dd, J 1 ) 3.9 Hz, J 2 ) 1.7 Hz, H-16), 2.29 (1H, dd, J 1 ) 10.5 Hz, J 2 ) 2. 4 Hz, H-13), 2.12 (1H, d, J ) 7.1 Hz, H-9), 1.93 (3H, s, MeCOO), 1.35 (d, J ) 7. 4 Hz, 3H-17), 0.98, 0.82 (3H each, s); 13…”

“…4 Hz, H-13), 2.12 (1H, d, J ) 7.1 Hz, H-9), 1.93 (3H, s, MeCOO), 1.35 (d, J ) 7. 4 Hz, 3H-17), 0.98, 0.82 (3H each, s); 13…”

“…Two hundred twentyeight mg of 5 was treated with benzoyl chloride/Py (1:2 mL). After 12 h at room temperature, the mixture was diluted with H 2 O, extracted with CHCl 3 , washed with saturated KHSO 4 Rearrangement of ent-18-Acetoxy-14R-(benzoyloxy)-15R,16R-epoxybeyerane (6). Product 6 (140 mg) was dissolved in CHCl 3 (5 mL) in a sealed tube.…”

“…Rearrangements of tetracyclic diterpenoids have been extensively studied and were carried out on epoxy compounds − or thiocarbonates or through solvolytic reactions. − Recent papers 8,9 have demonstrated that oxygenated functions near the epoxy group participate in the rearrangement process. Moreover, stereochemistry of this function may also influence the course of the reaction. , In previous papers, ruthenium-catalyzed rearrangements of epoxybeyeranes with 14- or 12-hydroxy and 14- or 12-acetoxy groups were reported. , In this paper, we investigate the possible participation of a benzoyloxy group in the intermediate structures formed in the rearrangement process and in the yields of products obtained.

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“…Rearrangements of tetracyclic diterpenoids have been extensively studied and were carried out on epoxy compounds [1][2][3][4][5][6][7][8][9] or thiocarbonates 10 or through solvolytic reactions. [11][12][13][14][15][16][17][18] Recent papers 8,9 have demonstrated that oxygenated functions near the epoxy group participate in the rearrangement process.…”