42465-57-6Relevant academic research and scientific papers
Camptothecin derivatives
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, (2008/06/13)
New campotothecin derivatives and a process for preparing same are disclosed, which are represented by the general formula: STR1 wherein R1 represents a lower alkyl group, R2 represents a hydrogen atom or an amino, hydroxyl, lower acylamino or lower alkoxy group, R3 represents a hydrogen or halogen atom or a lower alkyl, hydroxyl, lower alkoxy, nitro, amino, cyano or di(lower alkyl)amino group, R4 represents a hydrogen or halogen atom or a lower alkyl, hydroxyl, lower alkoxy, lower alkylthio, amino, cyano or di(lower alkyl)amino group, and R5 represents a hydrogen or halogen atom or a hydroxyl or lower alkoxy group, with the proviso that all of the R2, R3, R4 and R5 substituents should not be a hydrogen atom and also that if any one of the R2, R3, R4 and R5 is a hydroxyl or lower alkoxy group, all of the other three substituents should not be a hydrogen atom.
Alkaloid synthesis via the intramolecular imidate methylide 1,3-dipolar cycloaddition reaction
Smith, Richard,Livinghouse, Tom
, p. 3559 - 3568 (2007/10/02)
A concise synthesis for the neurotoxic physostigmine alkaloid d,l-eserethole is described which relys upon an intramolecular cycloaddition reaction involving a "non-stabilized" imidate methylide and an unactivated alkene. The facility of this cyclization
An Expedient Synthetic Approach to the Physostigmine Alkaloids via Intramolecular Formamidine Ylide Cycloadditions
Smith, Richard,Livinghouse, Tom
, p. 1554 - 1555 (2007/10/02)
New approaches for the direct generation of several highly reactive imidate methylides are described that rely upon acyl fluoride mediated desylilation.The utility of this methodology has been demonstrated in a stereospecific synthesis of dl-eserethole (4
