New Direct Synthesis of Persubstituted 4-Hydroxy-2-pyrones
作者:Giovanni Sartori、Franca Bigi、Davide Baraldi、Raimondo Maggi、Giuseppe Casnati、Xiaochun Tao
DOI:10.1055/s-1993-25952
日期:——
The synthesis of a series of persubstituted 4-hydroxy-2-pyrones 6 by regioselective "one-pot" cyclotrimerization of aliphatic acyl chlorides promoted by aluminum chloride is reported.
Inhibition of human leukocyte elastase, porcine pancreatic elastase, and chymotrypsin by elasnin and other 4-hydroxy-2-pyrones
作者:Robin W. Spencer、Leslie J. Copp、Jurg R. Pfister
DOI:10.1021/jm00150a013
日期:1985.12
Elasnin and 15 related 4-hydroxy-2-pyrones have been assayed for in vitro inhibition of human leukocyte elastase, porcine pancreatic elastase, and bovine chymotrypsin. Inhibition constants for HL elastase range from 0.1 to 10 mM. The principal determinant of potency against the elastases is probably the substituent at position 3, which may account for the observed strong homology between the elastases in their inhibition by these compounds. Acetylation of the 4-hydroxy group has no effect on inhibition. The inhibition is noncovalent; there is no evidence of enzyme acylation by these pyrones.
Friedel-crafts coordinated processes: Selective cyclooligomerization of acyl chlorides
Adducts AlCl3.RCOCl undergo highly regioselective self- and cross-condensation. 4-Hydroxy-2-pyrones and 2-acetyl-indan-1,3-diones are synthesized in good yields.
OSMAN M. A.; SEIBL J.; PRETSCH E., HELV. CHIM. ACTA <HCAC-AV>, 1977, 60, NO 8, 3007-3011