Many simple esters are responsible for the pleasant odours of fruits and flowers.
Additional research, in which OGp was replaced with simpler esters, indicated that besides enzyme recognition and affinity, the leaving group ability may be an important factor.
This usually involves borohydride mediated reduction of the acid moiety, followed by condensation/cyclisation of the resulting amino alcohol with a simple carbonate ester such as diethylcarbonate.
Ethyl pyruvate (EP) is a simple aliphatic ester derivative of pyruvic acid.
Together these observations demonstrate the importance of the fumarate pharmacophore and show that the anti-NFκB activity of GTCpFE goes beyond that of a simple ASA ester prodrug.
For this reason, current results which investigated ethyl pyruvate (EP), a simple aliphatic ester derived from pyruvate, seems very promising (Fink 2004; Zingarelli 2004).
A simple ethyl ester attachment to the methoxy group resulted in a 10-fold improvement in potency (7; IC50=1.6 μ m), and the crystal structure of the co-complex is consistent with the formation of the targeted hydrogen bond.
Such results could be explained by the effect of the nitro group, which stabilizes the negative charge in the phenolate anion, thus making the hydrolysis of the group easier and therefore this phosphoramidate prodrug has a shorter half-life compared to the corresponding phosphoramidate with the simple phenyl ester 3b.
It consists of the simple alkyl esters of fatty acids, most typically the methyl esters.
Although simple ethyl esters gave good yield but poor ee, the use of the BHT (butylated hydroxytoluene) ester resulted in formation of 76b in a remarkable 99% ee.
