Synthesis of simplified herboxidiene aromatic hybrids

Bioorganic and Medicinal Chemistry Letters

Volumn 10, Issue 12, 2000, Pages 1365-1368

  Edmunds, A J F ^a   Arnold, G ^a   Hagmann, L ^a   Schaffner, R ^a   Furlenmeier, H ^a  

^a NOVARTIS PHARMA AG   (Switzerland)

Author keywords

[No Author keywords available]

Indexed keywords

ALKENE DERIVATIVE; HERBICIDE;

ARTICLE; CHEMICAL MODIFICATION; PLANT; REACTION ANALYSIS; SYNTHESIS;

FATTY ALCOHOLS; HERBICIDES; PYRANS;

EID: 0034686505     PISSN: 0960894X     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0960-894X(00)00230-4     Document Type: Article

References (25)

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12. The tert-butyldimethylsilane (TBDMS) group was chosen as the protecting group to allow selective, mild deprotection at the final step in the syntheses. All attempts to directly add the TBDMS-protected Grignard to cyclopentanone failed, reduced Grignard being the only product obtained.
13. 2 even at low temperatures led to complex reaction mixtures.
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15. A mixture of the E and Z isomers can actually be used for the ring closure step but it was more convenient to separate isomers to simplify the GC analysis for this process. The effect of double bond geometry on kinetic intramolecular Michael addition reactions of this type has been reported. See; Banwell, M. G.; Bissett, B. D.; Bui, C. T.; Pham, Ha T. T.; Simpson, G. W. Aust. J. Chem. 1998, 51, 9.
16. As determined by gas chromatography analysis after thermodynamic equilibrium.
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20. Determined by HPLC analysis on a Chiracel OD-H column, eluting with 95:5 hexane:isopropyl alcohol.
21. 2, rt.
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23. 3).
24. -1. The plants were then further cultivated under optimal greenhouse conditions and after ca. 18 days the percentage plant damage rated by visual assessment.
25. The methyl ester of herboxidiene is actually more potent than the parent compound. See ref 1.