- To seek an approach toward the chemical conversion of C19- diterpenoid alkaloids to taxoids
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This study, as a part of conversion of the C19-diterpenoid alkaloids to the taxoids, described the search of a suitable route to the key intermediate B with four approaches (ABC, ACB, BCA, and CAB) designed and examined. In these cases, a new and efficient approach (CAB) toward the synthesis of the vital intermediates 51 or 52 has been developed. The key steps include the use of a semipinacol rearrangement treatment of 41 with NaOH/DMF under refluxing conditions for 30 min to afford 42, and the rupture of the N-C-19 bond found in 45 or 48 to give 51 or 52, respectively, through NBS imination followed by the creation of the oxaziridine 47 or the nitrone 50 and finally HIO4 oxidation cleavages.
- Wang, Feng-Peng,Xu, Liang
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p. 2149 - 2167
(2007/10/03)
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- Two new C19-diterpenoid alkaloids from Aconitum nagarum var. lasiandrum
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Further investigation on the phytochemistry of the plant Aconitum nagarum var. lasiandrum led to isolate two C19-diterpenoid alkaloids, francheline (1) and lasianine (3). Their structures were established on the basis of the spectral data.
- Ji, Hong,Chen, Dong-Lin,Wang, Feng-Peng
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p. 2363 - 2370
(2007/10/03)
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