Allergy-preventive effects of linarinic acid and its tetrahydropyrrolo[2,1-b]quinazoline derivatives isolated from Linaria vulgaris

Linarinic acid, (-)-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline-1-carboxylic acid (4a), was isolated from the ethanol extract of Linaria vulgaris Mill. In our previous study, a series of tetrahydropyrrolo[2,1-b]quinazoline derivatives 4b, 4c, 5a, 5b, 6a and 6b that were structurally related to 4a and evaluated as neuroprotective agents were synthesized. The aim of the present study was to investigate the novel features of these compounds. We...