Study On Syn-and Anti-perillartine By NMR

Perillartine(1,8-p-menthadiene-7-oxime) is a kind of sweetener with super strong effect whose degree is two thousands times of sucrose and ten times of glucide. It is used widely in making drinks, cakes , wine and cigarette and other foods . In the end of 1970s' , the perillartine was once imported from Japan and the price was very high even reach to RMB90, 000 per kilogram at that time .Nowadays, it is of great usefulness that acts as a sort of new super sweetener in the tobacco industry of China while aware of the efficacyof the perillartine .Since the sweet degree of the anti-perillartine is ten times of glucide while the syn-peri1lartine has no sweet taste,the quantity of anti-oxime in the product with synthesized sweetener becomes more important . However , there are no standard inspection methods and no report of analysis of separation of syn-anti isomerization of perillartine , and the kinetic research of it under different temperatures has not been undertaken .Regarding to above points, the followings have been taken up:(1) undertaking the analysis review by means of experimentation of HMQC, HMBC, H-H COSY, NOESY, DEPT and all the 'H and 13C NMR chemical shifts were assigned.(2) Experimentation on searching for perillar -tine under various circumstances:examine samples by heating the neat perillartine for some time a little above its melting point ; and examine samples after storing a long time in thetemperature of - 20;analyzing the differences between - OH and conformation of perillartine in the condition of different solvent^ concentra -tion and matching of different prorate of Benzene-d6/CC14 ;review of the influence of time, temperature, illumination on perillar -tine;(3) experiment by raising temperatures in DMSO, under 5℃, 10℃, 15℃, 20℃, 25℃, 30℃, 35 ℃, 40℃, 45℃, 50℃, 55℃, 60℃, 65℃, 70℃, 75 ℃,80℃,85℃,90℃ respectively; experiment by lowing temperatures in DMF, under 35℃, 25℃, 0℃,-16℃, -26℃, -36℃, -46 ℃ respectively. Finally, we observed the complete slow exchanging movement of perillartine under the temperature of 18.7 ℃, 29.7℃, 39.7℃, 49.7℃ successfully, and got the Kr, A G under different Tc.(4) Significant dependence of the ratio of E and Z isomers in the solvent of Benzene-d6 and CCL4 was observed . The E/Z ratio and the contents of impurity were given by the proton NMR spectrum.