Lessons from 1,3-Hydride Shifts in Sesquiterpene Cyclizations
作者:Jan Rinkel、Patrick Rabe、Paolina Garbeva、Jeroen S. Dickschat
DOI:10.1002/anie.201608042
日期:2016.10.17
initial 1,10‐cyclisation‐1,3‐hydride shift cascades. Enzymes with products of known absolute configuration showed a coherent stereochemical course, except for (−)‐α‐amorphene synthase, for which the obtained results are better explained by an initial 1,6‐cyclisation. The link between the absolute configuration of the product and the stereochemical course of the 1,3‐hydride shifts enabled assignment of
Antimalarial Properties of Simplified Kalihinol Analogues
作者:Mary Elisabeth Daub、Jacques Prudhomme、Choukri Ben Mamoun、Karine G. Le Roch、Christopher D. Vanderwal
DOI:10.1021/acsmedchemlett.7b00013
日期:2017.3.9
Several kalihinol natural products, members of the broader isocyanoterpene family of antimalarial agents, are potent inhibitors of Plasmodium falciparum, the agent of the most severe form of human malaria. Our previous total synthesis of kalihinol B provided a blueprint to generate many analogues within this family, some as complex as the natural product and some much simplified and easier to access. Each analogue was tested for blood-stage antimalarial activity using both drug-sensitive and -resistant P. falciparum strains. Many considerably simpler analogues of the kalihinols retained potent activity, as did a compound with a different decalin scaffold made in only three steps from sclareolide. Finally, one representative compound showed reasonable stability toward microsomal metabolism, suggesting that the isonitrile functional group that is critical for activity is not an inherent liability in these compounds.
Genome Mining in Streptomyces clavuligerus: Expression and Biochemical Characterization of Two New Cryptic Sesquiterpene Synthases
作者:Yunfeng Hu、Wayne K.W. Chou、Russell Hopson、David E. Cane
DOI:10.1016/j.chembiol.2010.11.008
日期:2011.1
Two presumptive terpene synthases of unknown biochemical function encoded by the sscg_02150 and sscg_03688 genes of Streptomyces clavuligerus ATCC 27074 were individually expressed in Escherichia coli as N-terminal-His(6)-tag proteins, using codon-optimized synthetic genes. Incubation of recombinant SSCG_02150 with farnesyl diphosphate (1, FPP) gave (-)-delta-cadinene (2) while recombinant SSCG_03688 converted FPP to (+)-T-muurolol (3). Individual incubations of (-)-delta-cadinene synthase with [1,1-H-2(2)]FPP (1a), (1S)-[1-H-2]-FPP (1b), and (1R)-[1-H-2]-FPP (1c) and NMR analysis of the resulting samples of deuterated (-)-delta-cadinene supported a cyclization mechanism involving the intermediacy of nerolidyl diphosphate (4) leading to a helminthogermacradienyl cation 5. Following a 1,3-hydride shift of the original H-1(si) of FPP, cyclization and deprotonation will give (-)-delta-cadinene. Similar incubations with recombinant SSCG_03688 supported an analogous mechanism for the formation of (+)-T-muurolol (3), also involving a 1,3-hydride shift of the original H-1(si) of FPP.
Bowden, Bruce F.; Coll, John C.; Willis, Richard H., Australian Journal of Chemistry, 1986, vol. 39, # 10, p. 1717 - 1722
作者:Bowden, Bruce F.、Coll, John C.、Willis, Richard H.