Preparation Of ?-linolenic Acid Polyhydroxy Derivatives

Alpha-linolenic acid in flaxseed oil is an essential fatty acid for sustaining human life.It is the"core member" of n-3 series unsaturated fatty acids and the most basic nutrient for life activities.Because of many unavoidable factors,it is difficult to supplement the human body lack of-linolenic acid.The main reasons are as follows:1.Lack of understanding of the biological activity and medicinal value of-linolenic acid.2.The high biological activity of-linolenic acid in foods cooked at high temperatures is unintentionally destroyed.-linolenic acid is highly reductive due to its 9,12,15-olefin structure and can be oxidized under high temperature,air oxygen,ultraviolet light and heavy metal ions.4.Alpha-linolenic acid taste bad and difficult to eat directly,poor water solubility,low bioavailability.Due to the high price of a-linolenic acid pure products,the low purity of industrial products makes it difficult to characterize,and the high reducibility of non-conjugated double bonds is vulnerable to acid,high temperature and other factors.In order to reduce the cost of the experiment,the approximate optimal conditions were determined by simulation experiments with lauric acid and tristearate glycerides,and then the exact conditions were studied by pure ?-linolenic acid.It was found in the experiment that when a-linolenic acid reacts with polyhydroxyl compounds(glucose,xylitol,glycerol,etc.),the presence of multiple hydroxyl groups will lead to the production of a large number of by-products due to the participation of many reaction sites to varying degrees.Therefore,we take the protection group placeholder only to expose the target hydroxyl group,and eventually remove the protection group to obtain the target compound.The-linolenic acid extracted from linseed oil was polyhydroxylated.The structure and purity of a-linolenic acid polyhydroxyl derivatives were analyzed by means of nuclear magnetic resonance instrument,TLC,HPLC etc.The contents of the paper are as follows:1.Analog Experimental Research Section1.1 Study on the Simulation of Polyhydroxyl Derivatives of Cinnamic AcidIncluding the synthesis of isopropyl fork polyhydroxyl compounds,the synthesis of lauric acid chloride,the synthesis of isopropyl lauric acid polyhydroxyl compounds,and the synthesis of lauric acid polyhydroxyl monoester compounds.1.2 Study of tristearic acid glyceride simulation experimentIncluding the exchange of tristearic acid glycerides with methanol esters to obtain methyl stearate,methyl stearate and isopropyl fork polyhydroxylated esters to obtain various isopropyl stearate polyhydroxyl compounds,stearate polyhydroxyl monoester compounds synthesis.2.Study on the synthesis of ?-linolenic acid polyhydroxyl derivativesIncluding 3-O-?-flaxyl-D-glucose(at 2%mol I2,65?,12 h yield 91%),1-a-linolenic acid simple Ester(yield 87%at 2%mol I2,65?,12 h),3-O-?-linolyl-xylitol(yield 82.4%at 2%mol I2,65?,12 h)alinolenic acid methyl Ester(Synthesis of 3 eq NEt3,5eqmethanol,acetonitrile,82?,8 h yield 85%).3.The optimum synthesis conditions of a-linolenic acid polyhydroxyl compounds were determined by using nuclear magnetism,HPLC,TLC,etc.According to experimental data,the industrial amplification design of the process synthesis route was carried out,and the related equipment type were initially selected.