Total Synthesis And Bio-activity Of Aggregation Pheromones Of Tribolium Castaneum Herbst

Tribolium castaneum is a pest that is widely harmful to the storage industry.This type of insect has a specific aggregation pheromone,which is synthesized from different stereoisomers of fatty aldehydes 4,8-dimethyldecal in a certain proportion.The structure of aliphatic hydrocarbon compounds is simple and diverse,and studies have shown that such compounds have certain attracting activity against such harmful insects.In order to develop new types of biogenic agricultural pesticides,in this paper,?S?-2-methyl butanol,gamma-butylactone,and chiral small molecules?R?-3-methyl-4-benzyloxy butyraldehyde,which were obtained by degradation of natural saponins,were used as raw materials to synthesize the key carbon chain skeleton of the pheromone skeleton.Based on the synthesis of the skeleton,a series of different stereoisomers of the pheromones collected by the larceny were obtained,and they were used to determine the biological activity of the adults in the larceny test.The main research contents and results of this paper are as follows:1.Firstly,Carried out the exploration of the all-synthetic route of the racemic pheromone.We take cheap 3-bromopropionic acid,4-bromobutyric acid,5-bromopentanoic acid and so on as raw materials respectively to construct C-C skeleton by Wittig reaction.After 11 steps,10 steps,and 9 steps respectively,linear synthesis was completed,and all of them have achieved the racemization of the aggregation pheromone of the photoretrix with a yield of more than 20%.The target product 4,8-dimethyldecanal can be obtained from all three routes,and a total of 26intermediates were prepared,and 5 new structures that have not been reported.2.Conducted the chiral synthesis route of the aggregation pheromone.In this paper,we use the cheap?-butyrolactone as the initial material to prepare the intermediate4-benzyloxybutyric acid by ring opening reaction,and constructing a chiral center using asymmetric alkylation of Evans.The C-C skeleton is constructed by the alkyl reaction of Julia,and after a linear 12-step reaction,the target product?4S,8S?-4,8-dimethyldecaraldehyde and?4R,8S?-4,8-dimethyldecaraldehyde were synthesized with a total yield of 21%and 20%respectively.A total of 24 intermediates were prepared,of which 10 new structures have not been reported.3.Based on the concept of resource chemistry,we used chiral small molecule fragment?R?-3-methyl-4-benzyloxybutyraldehyde as raw materials,which were obtained by the degradation of steroidal saponins in the study group of Professor Weisheng Tian of the Shanghai Institute of Organic Chemistry.After the linear 9-step reaction,the total synthesis of the pheromones?4R,8R?-4,8dimethyldecaraldehyde was completed with a total yield of more than 30%.4.According to the natural aggregation pheromone component of the Tribolium castaneum,we use 2-methylbutyraldehyde and 4-bromobutyric acid as raw materials to construct a chiral center by using the asymmetric alkylation reaction model of Evans.The C-C skeleton was constructed by Wittig reaction,and the synthesis of the natural Tribolium castaneum was completed by a linear 11-step reaction with a total yield of more than 35%.The product is a natural mixture consisting of?4R,8R?-4,8-dimethyldecanal,?4R,8S?-4,8-dimethyldecanal,?4S,8R?-4,8-dimethyldecanal and?4S,8S?-4,8-dimethyldecanal,and the ratio of them is 4 to 4 to 1 to 1.A total of 10intermediates were prepared,of which 8 structures have not been reported.5.The 72 compounds synthesized in this paper contain stereoisomer structures,all of which were characterized by ¹H-NMR and ¹³C-NMR,and all the products containing optical rotation have been tested for optical rotation values.Some chiral molecules induced by Evans template were detected by HPLC,and their d.r.values were all greater than 90%.6.Using the"trap"two-way selection method to test the behavioral response of the test worms to the above synthetic products.Through the test results of the synthetic product on the biological inducement activity of the insects,it was proved that the target products?4R,8S?-5-1 and 6-1 with chiral structure had attractive activity against the Tribolium castaneum Herbst,and the target product of the synthesis is that the mixture of 4-1 has a strong inducement to the insect.