The New C-2,C-3 Substituted Heterocyclic Derivatives of L-Ascorbic acid: Synthesis, Characterization, and Bacterial Activity

الملخص

New Schiff bases derivatives [IV]a-e is prepared via condensation of Derythroascorbic
acid with p-substituted aldehydes in dry benzene. To obtain these
derivatives, the 5,6-O-isopropylidene-L-ascorbic acid[I] was chosen as starting material,
compound prepared from the reaction of L-ascorbic acid as starting material.
Compound[I] was prepared from the reaction of L-ascorbic acid with dry acetone in the
presence of hydrogen chloride. The esterification of hydroxyl groups at C-2 and C-3
positions with excess ofethyl α –chloroacetate in the presence of sodium acetate produce
acorresebonding ester [II] , which was condensed with hydrazine hydrate to give new
hydrazide [III] . The new Schiff bases [IV]a-e were synthesized by reaction of acid
hydrizide with different p-substituted benzaldehyde in dry benzene . The new 1,3-
oxazepine derivatives [V]a-ewere obtained by Diels-Alder reaction of Schiff bases with
phthalic anhydride in dry benzene (Scheme 1) . All the synthesized compounds have
been characterized by melting points , FTIR and 1HMNR (of some of theme)
spectroscopy. The biological activity of synthesized compounds was examined against
two types of bacteria; G(+) and G(-).
Key words : L- ascorbic acid, Hydrazied, Schiff bases, 1,3-Oxazepine.