15272-24-9Relevant academic research and scientific papers
Enantioselective Synthesis and Absolute Configuration of (R)-(+)-Lunacridine and (S)-(+)-Lunacrine
Anand, Ramesh C.,Selvapalam, N.
, p. 126 - 142 (2007/10/03)
(R)-(-)-Lunacridine 1 has been synthesized in 97.3percent e.e. using a chiron approach through L-valine and D-mannitol as the starting compounds to corroborate its absolute configuration.The key intermediate (S)-1,2-epoxy-3-methylbutane 11 was synthesized from (L)-valine (3 -> -> 11) and a (D)-mannitol derivative (12 -> -> 11) via functional group manipulation.The epoxide 11 was reacted with lithiated 2,4,8-trimethoxyquinoline 17 and the resulting product 18 was selectively deprotected at the 2-position followed by N-methylation of 19 to give 1.In an alternative strategy 11 was transformed into the THP-acid 23 through the chiral lactone 20.Condensation of 23 with substituted methyl anthranilate gave the amide 24 which on cyclisation, methylation and deprotection steps sequentially afforded 1.
A Convenient Preparation of 4,8-Dimethoxy-3-substituted-2(1H)-quinolones by an Electrophilic Reaction through Base-induced Deprotonation and its Synthetic Application for the Synthesis of New Alkaloids, 3,4,8-Trimethoxy-2(1H)-quinolone and 3-Formyl-4,7,8-trimethoxy-2(1H)-quinolone(Glycocitridine)
Tagawa, Yoshinobu,Kawaoka, Takamitsu,Goto, Yoshinobu
, p. 1677 - 1683 (2007/10/03)
Some 4,8-dimethoxy-3-substituted-2(1H)-quinolones were prepared by electrophilic reaction of 4,8-dimethoxy-2(1H)-quinolone with electrophiles in the presence of n-butyllithium-N,N,N',N',-tetramethylethylenediamine in fairly good yields. This present method was successfully applied for the synthesis of two new alkaloids bearing the 4,8-dimethoxy-2(1H)-quinolone skeleton.
