高甜度二肽甜味剂的合成与特性

以异香兰素为原料,经Wittig反应、常温常压催化氢化、二异丁基氢化铝还原制得中间体3-(3-羟基-4-甲氧基苯基)丙醛。S-叔丁基-L-半胱氨酸甲酯与N-叔丁氧羰基-L-天冬氨酸-4-叔丁酯经1-乙基-(3-二甲基氨基丙基)碳酰二亚胺盐酸盐以及1-羟基苯并三唑水合物缩合制得二肽化合物N-(N-叔丁氧羰基-4-叔丁酯-L-α-天冬氨酰)-S-叔丁基-L-半胱氨酸-1-甲酯,并在氯化氢-二氧六环溶液中脱保护制得二肽化合物N-(L-α-天冬氨酰)-S-叔丁基-L-半胱氨酸-1-甲酯;然后将中间体3-(3-羟基-4-甲氧基苯基)丙醛与N-(L-α-天冬氨酰)-S-叔丁基-L-半胱氨酸-1-甲酯通过亚胺化钯碳氢气常压催化氢化得到目标化合物N-N-3-(3-羟基-4-甲氧基苯基)丙基]-L-α-天冬氨酰基]-S-叔丁基-L-半胱氨酸-1-甲酯。经红外光谱、质谱以及核磁共振仪对产物进行结构鉴定,确定目标产物结构。

Synthesis and Characterization of High-Potency Dipeptide Sweetener

N-N-3-(3-hydroxy-4-methoxyphenyl)propyl]-L-α-aspartyl]-S-tert-butyl-L-cysteine-1-methyl ester, a high-potency dipeptide sweetener, is approximately 40 000 times sweeter than sucrose. 3-(3-Hydroxy-4-methoxyphenyl) propanal was synthesized from isovanillin through Wittig reaction, catalytic hydrogenation at room temperature and ambient pressure and reduction with diisobutylaluminium hydride (DIBAL-H). A dipeptide was synthesized from S-tert-butyl-L-cysteine-methyl ester and N-(tert-butoxycarbonyl)-L-aspartic acid-4-tert-butyl ester coupled with 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) and 1-hydroxybenzotriazole (HOBt) by condensation reaction. N-(L-α-aspartyl)-S-tert-butyl-L-cysteine-1-methyl ester was prepared by dissolving the dipeptide in hydrochloric acid (HCl)-dioxane solvent. Finally, 3-(3-hydroxy-4-methoxyphenyl)propanal was reacted with N-(L-α-aspartyl)-S-tert-butyl-L-cysteine-1-methyl ester through palladium on carbon (Pd/C)-catalyzed hydrogenation at room temperature and ambient pressure to obtain N-N-3-(3-hydroxy-4-methoxyphenyl)propyl]-L-α-aspartyl]-S-tert-butyl-L-cysteine-1-methyl ester. The structure of the final product was identified by infrared spectroscopy, mass spectrometry and nuclear magnetic resonance.