A new pyrone strategy for the synthesis of 3-acyltetramic acids
作者:Raymond C.F. Jones、Jacqueline M. Patience
DOI:10.1016/s0040-4039(00)99205-0
日期:——
The potential of pyrones as precursors to 3-acyltetramic acids has been demonstrated by the conversion of 5-ethoxycarbonyl-4-methoxy-6-methyl-2-pyrone into a 3-acetyltetramic acid.
Selective reduction of the 5-carbomethoxy- and the 5-carbethoxy-4-hydroxy-2H-pyran-2-one derivatives (5a approximately 11, 19) to yield the 5-hydroxymethyl derivatives (12 approximately 18) was accomplished using 1.1 mol equivalent of borane-methyl sulfide complex. Additionally, reduction of the 3-acetyl-4-hydroxy-2H-pyran-2-one derivatives (23, 26 and 29) with borane-methyl sulfide complex afforded the binary condensed pyrone derivatives (25, 28 and 3 1) in good yields.
Total Synthesis of Islandic Acid I Methyl Ester, Rosellisin and Rosellisin Aldehyde
Total synthesis of islandic acid I methyl ester (2), rosellisin (3) and rosellisin aldehyde (4) has been accomplished starting from 4-hydroxy-5-hydroxymethyl-6-methyl-2H-pyran-2-one (9a) via formylation of 9a with dichloromethyl methyl ether and titanium tetrachloride as a key step.
JONES, RAYMOND C. F.;PATIENCE, JACQUELINE M., TETRAHEDRON LETT., 30,(1989) N4, C. 3217-3218