We designed 1-alkyloxygenipins with the aim of improving the stability of genipins based on the structural and electronic properties of genipins, and prepared 1-alkyloxygenipins and examined their neuritogenic activities in PC12h cells. All genipin-derivatives exhibited electronic properties similar to those of genipin and induced significant neurite outgrowth. These compounds will be classified as nitric oxide synthase (NOS) activators (neuritogenic active compounds) since their lowest unoccupied molecular orbital (LUMO)-energies are similar to that of tetrahydrobiopterin (H4B). (1R)-isoPropyloxygenipin showed activity comparable to that of genipin, and unlike the parent compound genipin, it was found to be physiologically stable in rat liver homogenate.
Stereoselective Reduction of 1-<i>O</i>-Isopropyloxygenipin Enhances Its Neuroprotective Activity in Neuronal Cells from Apoptosis Induced by Sodium Nitroprusside
rat adrenal pheochromocytoma (PC12) and retinal neuronal (RGC‐5) cellsfrom injury induced by sodiumnitroprusside (SNP). The neuroprotective effects of CHR20 and CHR21 were greater than both isomers of IPRG001, the parent compounds. These results indicate that reduction of 1‐O‐isopropyloxygenipin enhancesitsneuroprotectiveactivity without affecting its stability.