Recent applications of the divinylcyclopropane–cycloheptadiene rearrangement in organic synthesis

• Sebastian Krüger and
• Tanja Gaich

Beilstein J. Org. Chem. 2014, 10, 163–193, doi:10.3762/bjoc.10.14

• place prior to the rearrangement to access the required boat transition state of the rearrangement. Intermediate 58 was converted to the natural product 59 in four additional steps. Two other sesquiterpenoids, prezizaene (63) [59][60] and prezizanol (64) [60], isolated from Eremophilia georgei or

Lanostane- and cycloartane-type triterpenoids from Abies balsamea oleoresin

• Serge Lavoie,
• Charles Gauthier,
• Jean Legault,
• Sylvain Mercier,
• Vakhtang Mshvildadze and
• André Pichette

Beilstein J. Org. Chem. 2013, 9, 1333–1339, doi:10.3762/bjoc.9.150

• remedy, and venereal aid [4]. In recent years, we have become interested in studying the bioactive constituents of A. balsamea. Our work allowed the identification of antibacterial sesquiterpenoids, active against S. aureus, from balsam fir essential oil [5]. We also isolated two cytotoxic

Caryolene-forming carbocation rearrangements

• Quynh Nhu N. Nguyen and
• Dean J. Tantillo

Beilstein J. Org. Chem. 2013, 9, 323–331, doi:10.3762/bjoc.9.37

• intermediates; terpene; Introduction The cytotoxic sesquiterpenol caryol-1(11)-en-10-ol (1, Figure 1) was isolated by Barrow et al. in 1988 during an investigation of antiviral/antitumor compounds from New Zealand marine invertebrates [2]. Similar sesquiterpenoids were also found in Campanella fungi

• isotropic values into chemical shifts [11][12][13]. Caryol-1(11)-en-10-ol (1) and similar sesquiterpenoids. Note that a different atom numbering was used in the paper describing the isolation of 1 [2]. Computed (top) and experimental (bottom, underlined italics) [2] 1H and 13C chemical shifts for 1 (lowest

Carbamate derivatives and sesquiterpenoids from the South China Sea gorgonian Melitodes squamata

• Li-Si Huang,
• Fei He,
• Hui Huang,
• Xiao-Yong Zhang and
• Shu-Hua Qi

Beilstein J. Org. Chem. 2012, 8, 170–176, doi:10.3762/bjoc.8.18

• (1, 2), dimethyl ((carbonylbis(azanediyl))bis(2-methyl-5,1-phenylene))dicarbamate (3), obtucarbamates A and B (4, 5), and four aromadendrane-type sesquiterpenoids, (+)-4β-N-methenetauryl-10β-methoxy-1β,5α,6β,7β-aromadendrane (6), (−)-4β-N-methenetauryl-10β-methoxy-1β,5β,6α,7α-aromadendrane (7

• rarely found in marine natural compounds, and 7 showed moderate antibacterial activity. The possible biosynthesis routes of 1–5 were conjectured. Keywords: carbamate; gorgonian; Melitodes squamata; sesquiterpenoid; Introduction Gorgonians are recognized to mainly produce acetogenins, sesquiterpenoids

• aromadendrane-type sesquiterpenoids, (+)-4β-N-methenetauryl-10β-methoxy-1β,5α,6β,7β-aromadendrane (6), (−)-4β-N-methenetauryl-10β-methoxy-1β,5β,6α,7α-aromadendrane (7), (−)-4α,10β-aromadendranediol) (8) [7], (+)-4β,10β-aromadendranediol) (9) [7] (Figure 1) from the EtOH/CH2Cl2 extracts of M. squamata. Compounds

Toward an integrated route to the vernonia allenes and related sesquiterpenoids

• Da Xu,
• Michael A. Drahl and
• Lawrence J. Williams

Beilstein J. Org. Chem. 2011, 7, 937–943, doi:10.3762/bjoc.7.104