Article | Published:

Total synthesis of solanoeclepin A

Nature Chemistry volume 3, pages 484488 (2011) | Download Citation

Abstract

Cyst nematodes are troublesome parasites that live on, and destroy, a range of important host vegetable plants. Damage caused by the potato cyst nematode has now been reported in over 50 countries. One approach to eliminating the problem is to stimulate early hatching of the nematodes, but key hatching stimuli are not naturally available in sufficient quantities to do so. Here, we report the first chemical synthesis of solanoeclepin A, the key hatch-stimulating substance for potato cyst nematode. The crucial steps in our synthesis are an intramolecular cyclization reaction for construction of the highly strained tricyclo[5.2.1.01,6]decane skeleton (DEF ring system) and an intramolecular Diels–Alder reaction of a furan derivative for the synthesis of the ABC carbon framework. The present synthesis has the potential to contribute to addressing one of the critical food issues of the twenty-first century.

  • Compound C27H30O9

    Solanoeclepin A

  • Compound C13H17NO2

    (1R,4S,7aS)-1-Cyano-7a-methyl-2,4,5,6,7,7a-hexahydro-1H-inden-4-yl acetate

  • Compound C13H17NO3

    (1aR,3R,3aS,7S,7aS)-3-Cyano-3a-methyloctahydroindeno[1,7a-b]oxiren-7-yl acetate

  • Compound C13H17NO3

    (1R,3aR,4S,7aS)-1-Cyano-7a-methyl-3-oxooctahydro-1H-inden-4-yl acetate

  • Compound C13H17NO

    (1R,3R,7aS)-3-Hydroxy-7a-methyl-3-vinyl-2,3,5,6,7,7a-hexahydro-1H-indene-1-carbonitrile

  • Compound C13H17NO2

    (1aR,4aS,5R,7R,7aS)-7-Hydroxy-4a-methyl-7-vinyloctahydroindeno[3a,4-b]oxirene-5-carbonitrile

  • Compound C13H17NO2

    (1R,3aS,4R,7aS)-4-Hydroxy-7a-methyl-3-oxo-3a-vinyloctahydro-1H-indene-1-carbonitrile

  • Compound C25H47NO3Si2

    (1R,3S,3aR,4R,7aS)-3,4-Bis((tert-butyldimethylsilyl)oxy)-7a-methyl-3a-((S)-oxiran-2-yl)octahydro-1H-indene-1-carbonitrile

  • Compound C31H61NO3Si3

    (1S,3S,3aS,4R,7aS)-3,4-Bis((tert-butyldimethylsilyl)oxy)-8-(((tert-butyldimethylsilyl)oxy)methyl)-7a-methyloctahydro-1,3a-methanoindene-1-carbonitrile

  • Compound C35H68O5Si3

    (E)-Ethyl 3-((1S,3S,3aS,4R,7aS)-3,4-bis((tert-butyldimethylsilyl)oxy)-8-(((tert-butyldimethylsilyl)oxy)methyl)-7a-methyloctahydro-1,3a-methanoinden-1-yl)acrylate

  • Compound C34H68O4Si3

    ((1R,2R)-2-((1S,3S,3aS,4R,7aS)-3,4-Bis((tert-butyldimethylsilyl)oxy)-8-(((tert-butyldimethylsilyl)oxy)methyl)-7a-methyloctahydro-1,3a-methanoinden-1-yl)cyclopropyl)methanol

  • Compound C35H60O4Si2

    ((1S,3S,3aS,4R,7aS)-1-((1R,2R)-2-((Benzyloxy)methyl)cyclopropyl)-3,4-bis((tert-butyldimethylsilyl)oxy)-7a-methyloctahydro-1,3a-methanoinden-8-yl)methanol

  • Compound C35H58O3Si2

    (((1S,3S,3aS,4R,7aS)-1-((1R,2R)-2-((Benzyloxy)methyl)cyclopropyl)-7a-methyl-8-methyleneoctahydro-1,3a-methanoindene-3,4-diyl)bis(oxy))bis(tert-butyldimethylsilane)

  • Compound C23H28O3

    (1S,3S,3aR,7aS)-1-((1R,2R)-2-((Benzyloxy)methyl)cyclopropyl)-3-hydroxy-7a-methyl-8-methylenehexahydro-1,3a-methanoinden-4(1H)-one

  • Compound C34H41NO4

    (1S,3S,3aR,7aS,E)-3-((Benzyloxy)methoxy)-1-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-5-((dimethylamino)methylene)-7a-methyl-8-methylenehexahydro-1,3a-methanoinden-4(1H)-one

  • Compound C33H35F3O7S

    (1S,3S,3aR,7aS)-3-((Benzyloxy)methoxy)-1-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-5-formyl-7a-methyl-8-methylene-1,2,3,6,7,7a-hexahydro-1,3a-methanoinden-4-yl trifluoromethanesulfonate

  • Compound C41H49F3O9SSi

    (1S,3S,3aR,7aS)-3-((Benzyloxy)methoxy)-1-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-5-((R)-hydroxy(4-methoxy-5-(trimethylsilyl)furan-2-yl)methyl)-7a-methyl-8-methylene-1,2,3,6,7,7a-hexahydro-1,3a-methanoinden-4-yl trifluoromethanesulfonate

  • Compound C41H49F3O9SSi

    (1S,3S,3aR,7aS)-3-((Benzyloxy)methoxy)-1-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-5-((R)-(4-methoxyfuran-2-yl)((trimethylsilyl)oxy)methyl)-7a-methyl-8-methylene-1,2,3,6,7,7a-hexahydro-1,3a-methanoinden-4-yl trifluoromethanesulfonate

  • Compound C46H58O7Si

    1-((1S,3S,3aR,7aS)-3-((Benzyloxy)methoxy)-1-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-5-((R)-(4-methoxyfuran-2-yl)((trimethylsilyl)oxy)methyl)-7a-methyl-8-methylene-1,2,3,6,7,7a-hexahydro-1,3a-methanoinden-4-yl)-4-methylpent-3-en-2-one

  • Compound C46H58O7Si

    (1S,3S,3aS,6R,6aR,9R,10aR,12bR)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-8-methoxy-3a,10,10-trimethyl-13-methylene-6-((trimethylsilyl)oxy)-1,2,3,3a,4,5,9,10,10a,12-decahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]ind-11(6H)-one

  • Compound C42H46O7

    (1S,3S,3aS,6aR,9R,10aR,12bR)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-3a,10,10-trimethyl-13-methylene-1,2,3,3a,4,5,10,10a-octahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-6,8,11(7H,9H,12H)-trione

  • Compound C42H44O8

    (1S,3S,3aS,6aR,9R,12bS)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-11-hydroxy-3a,10,10-trimethyl-13-methylene-1,2,3,3a,4,5,9,10-octahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-6,8,12(7H)-trione

  • Compound C43H46O8

    (1S,3S,3aS,6aR,9R,12bS)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-11-methoxy-3a,10,10-trimethyl-13-methylene-1,2,3,3a,4,5,9,10-octahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-6,8,12(7H)-trione

  • Compound C43H50O8

    (1S,3S,3aS,6S,6aR,8R,9R,12bS)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-6,8-dihydroxy-11-methoxy-3a,10,10-trimethyl-13-methylene-1,2,3,3a,4,5,7,8,9,10-decahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]inden-12(6H)-one

  • Compound C43H52O8

    (1S,3S,3aS,6S,6aR,8R,9R,12bS)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-11-methoxy-3a,10,10-trimethyl-13-methylene-1,2,3,3a,4,5,6,7,8,9,10,12-dodecahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-6,8,12-triol

  • Compound C43H48O8

    (1S,3S,3aS,6S,6aR,9R,12bS)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-6-hydroxy-11-methoxy-3a,10,10-trimethyl-13-methylene-1,2,3,3a,4,5,9,10-octahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-8,12(6H,7H)-dione

  • Compound C46H56O8Si

    (1S,3S,3aS,6S,6aR,9R,12bS)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-11-methoxy-3a,10,10-trimethyl-13-methylene-6-((trimethylsilyl)oxy)-1,2,3,3a,4,5,9,10-octahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-8,12(6H,7H)-dione

  • Compound C42H46O9

    (1S,3R,3aS,6S,6aR,9R,12bR)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-6-hydroxy-11-methoxy-3a,10,10-trimethyl-1,2,3,3a,4,5,9,10-octahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-8,12,13(6H,7H)-trione

  • Compound C45H54O9Si

    (1S,3R,3aS,6S,6aR,9R,12bR)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-11-methoxy-3a,10,10-trimethyl-6-((trimethylsilyl)oxy)-1,2,3,3a,4,5,9,10-octahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-8,12,13(6H,7H)-trione

  • Compound C30H40O8Si

    (1S,3R,3aS,6S,6aR,9R,12bR)-1-Hydroxy-3-((1R,2R)-2-(hydroxymethyl)cyclopropyl)-11-methoxy-3a,10,10-trimethyl-6-((trimethylsilyl)oxy)-1,2,3,3a,4,5,9,10-octahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-8,12,13(6H,7H)-trione

  • Compound C33H48O8Si2

    (1S,3R,3aS,6S,6aR,9R,12bR)-3-((1R,2R)-2-(Hydroxymethyl)cyclopropyl)-11-methoxy-3a,10,10-trimethyl-1,6-bis((trimethylsilyl)oxy)-1,2,3,3a,4,5,9,10-octahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-8,12,13(6H,7H)-trione

  • Compound C33H46O8Si2

    (1R,2R)-2-((1S,3R,3aS,6S,6aR,9R,12bR)-11-Methoxy-3a,10,10-trimethyl-8,12,13-trioxo-1,6-bis((trimethylsilyl)oxy)-1,2,3,3a,4,5,6,7,8,9,10,12-dodecahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]inden-3-yl)cyclopropanecarbaldehyde

  • Compound C33H46O9Si2

    (1R,2R)-2-((1S,3R,3aS,6S,6aR,9R,12bR)-11-Methoxy-3a,10,10-trimethyl-8,12,13-trioxo-1,6-bis((trimethylsilyl)oxy)-1,2,3,3a,4,5,6,7,8,9,10,12-dodecahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]inden-3-yl)cyclopropanecarboxylic acid

  • Compound C11H13NO

    (1R,7aS)-7a-Methyl-3-oxo-2,3,5,6,7,7a-hexahydro-1H-indene-1-carbonitrile

  • Compound C13H19NO2

    (1R,3S,3aS,4R,7aS)-3,4-Dihydroxy-7a-methyl-3a-vinyloctahydro-1H-indene-1-carbonitrile

  • Compound C25H47NO2Si2

    (1R,3S,3aS,4R,7aS)-3,4-Bis((tert-butyldimethylsilyl)oxy)-7a-methyl-3a-vinyloctahydro-1H-indene-1-carbonitrile

  • Compound C31H62O4Si3

    (1S,3S,3aS,4R,7aR)-3,4-bis((tert-Butyldimethylsilyl)oxy)-8-(((tert-butyldimethylsilyl)oxy)methyl)-7a-methyloctahydro-1,3a-methanoindene-1-carbaldehyde

  • Compound C33H66O4Si3

    (E)-3-((1S,3S,3aS,4R,7aS)-3,4-bis((tert-Butyldimethylsilyl)oxy)-8-(((tert-butyldimethylsilyl)oxy)methyl)-7a-methyloctahydro-1,3a-methanoinden-1-yl)prop-2-en-1-ol

  • Compound C41H74O4Si3

    (((1S,3S,3aS,4R,7aS)-1-((1R,2R)-2-((Benzyloxy)methyl)cyclopropyl)-8-(((tert-butyldimethylsilyl)oxy)methyl)-7a-methyloctahydro-1,3a-methanoindene-3,4-diyl)bis(oxy))bis(tert-butyldimethylsilane)

  • Compound C41H63NO5SeSi2

    (((1S,3S,3aS,4R,7aS)-1-((1R,2R)-2-((Benzyloxy)methyl)cyclopropyl)-7a-methyl-8-(((2-nitrophenyl)selanyl)methyl)octahydro-1,3a-methanoindene-3,4-diyl)bis(oxy))bis(tert-butyldimethylsilane)

  • Compound C23H30O3

    (1S,3S,3aS,4R,7aS)-1-((1R,2R)-2-((Benzyloxy)methyl)cyclopropyl)-7a-methyl-8-methyleneoctahydro-1,3a-methanoindene-3,4-diol

  • Compound C29H44O3Si

    (1S,3S,3aS,4R,7aS)-1-((1R,2R)-2-((Benzyloxy)methyl)cyclopropyl)-3-((tert-butyldimethylsilyl)oxy)-7a-methyl-8-methyleneoctahydro-1,3a-methanoinden-4-ol

  • Compound C29H42O3Si

    (1S,3S,3aR,7aS)-1-((1R,2R)-2-((Benzyloxy)methyl)cyclopropyl)-3-((tert-butyldimethylsilyl)oxy)-7a-methyl-8-methylenehexahydro-1,3a-methanoinden-4(1H)-one

  • Compound C31H36O4

    (1S,3S,3aR,7aS)-3-((Benzyloxy)methoxy)-1-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-7a-methyl-8-methylenehexahydro-1,3a-methanoinden-4(1H)-one

  • Compound C38H41F3O9S

    (1S,3S,3aR,7aS)-3-((Benzyloxy)methoxy)-1-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-5-((R)-hydroxy(4-methoxyfuran-2-yl)methyl)-7a-methyl-8-methylene-1,2,3,6,7,7a-hexahydro-1,3a-methanoinden-4-yl trifluoromethanesulfonate

  • Compound C42H48O7

    (1S,3S,3aS,6R,6aR,9R,10aR,12bR)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-6-hydroxy-3a,10,10-trimethyl-13-methylene-1,2,3,3a,4,5,9,10,10a,12-decahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-8,11(6H,7H)-dione

  • Compound C42H46O8

    (1S,3S,3aS,6aR,9R,10aR,12bS)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-12-hydroxy-3a,10,10-trimethyl-13-methylene-1,2,3,3a,4,5,10,10a-octahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-6,8,11(7H,9H,12H)-trione

  • Compound C43H50O10

    (1S,3R,3aS,6S,6aR,9R,12bR)-1-((Benzyloxy)methoxy)-3-((1R,2R)-2-((benzyloxy)methyl)cyclopropyl)-6,13-dihydroxy-13-(hydroxymethyl)-11-methoxy-3a,10,10-trimethyl-1,2,3,3a,4,5,9,10-octahydro-6a,9-epoxy-3,12b-methanobenzo[4,5]cyclohepta[1,2-e]indene-8,12(6H,7H)-dione

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Acknowledgements

The authors thank Prof. T. Inabe (Hokkaido University) for X-ray diffraction measurements. This research was partly supported by the Global COE Program (project no. B01: Catalysis as the basis for innovation in materials science) and a Grant-in-Aid for Scientific Research on Innovative Areas (project no. 2105: Organic synthesis based on reaction integration) from the Ministry of Education, Culture, Sports, Science, and Technology, Japan.

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Affiliations

  1. Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan

    • Keiji Tanino
    • , Motomasa Takahashi
    • , Yoshihide Tomata
    •  & Hiroshi Tokura
  2. National Agriculture Research Center for Hokkaido Region, Sapporo 062-8555, Japan

    • Taketo Uehara
    •  & Takashi Narabu
  3. Faculty of Engineering, Kogakuin University, Hachioji, Tokyo 192-0015, Japan

    • Masaaki Miyashita

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Contributions

K.T. and M.M. conceived the experiments and analysed the results. M.T., Y.T. and H.T. performed the laboratory experiments and optimized the reaction conditions. T.U. and T.N. performed biological testing and evaluation of synthetic solanoeclepin A. K.T. and M.M. wrote the paper.

Competing interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to Keiji Tanino or Masaaki Miyashita.

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DOI

https://doi.org/10.1038/nchem.1044

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