Total synthesis of (+)-spiculoic acid A

Tetrahedron Letters

Volumn 50, Issue 26, 2009, Pages 3356-3358

  Matsumura, Daisuke ^a   Toda, Takumi ^a   Hayamizu, Takashi ^a   Sawamura, Kiyoto ^a   Takao, Ken ichi ^a   Tadano, Kin ichi ^a  

^a KEIO UNIVERSITY   (Japan)

Author keywords

(+) Spiculoic acid A; Cytotoxicity; Intramolecular Diels Alder reaction; Marine natural product; Suzuki Miyaura coupling; Total synthesis

Indexed keywords

2,7,9 DODECANAL; ALDEHYDE DERIVATIVE; INDAN DERIVATIVE; KETONE DERIVATIVE; NATURAL PRODUCT; POLYKETIDE; SPICULOIC ACID A; TETRAHYDROINDAN 2 ONE; UNCLASSIFIED DRUG;

ARTICLE; CROSS COUPLING REACTION; DIELS ALDER REACTION; DRUG CYTOTOXICITY; DRUG STRUCTURE; DRUG SYNTHESIS; QUANTUM YIELD; STEREOCHEMISTRY;

ALNUS;

EID: 65549158304     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2009.02.101     Document Type: Article

References (29)

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9. Although the IMDA approach to the total synthesis of (-)-spiculoic acid A disclosed by the Baldwin/Lee group was straightforward for the construction of the bicyclic structure possessing all the requisite functionalities, the desired cycloadduct was obtained in a less satisfactory yield of 25% (100 °C in toluene).
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20. As the spontaneous IMDA reaction started at 70 °C under the Suzuki-Miyaura coupling conditions, we kept continuing the IMDA reaction at 70 °C. The IMDA reaction of 23 proceeded at 70 °C rather slowly but cleanly. For completion of the IMDA reaction, it required 5 days. After heating for 1 or 2 days at 70 °C, substantial amount of 23 remained intact. We did not execute the IMDA reaction at other temperatures.
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