Study On New Optical Compounds Of The N-acylalanines

N-Acylalanines belong to a series of systemic fungicides with high activity, low toxicity and residual action. They possess the natures of prevention and care of plant from Peronsporales infection. The general structure of the N-acylalanines as fungicide is following:N-C(C)-C in the molecular structure is the fungicidally active radical. For achieving high biological activity of the fungicides, it is essential to remain the active radical, change R radical to form a series of new compounds. In the fungicidally active radical, there is one chiral C, so exist one pair of enantiomeric isomers. The fungicidal activities are different in enantiomeric isomers.The insecticide of dichloro-chrysanthemic acid (DCCA) is a kind of bio-source insecticides - a important kind of pyrethroid. They can achieve good effect in controlling insects on vegetables, fruit trees and other economic trees. Many of them have stability to light. The general structure of the DCCA as insecticide is following:The insecticides of DCCA divide into insecticides of trans -dichloro-chrysanthemic acid (trans- DCCA) and cis- dichloro-chrysanthemic acid (cis- DCCA) and the latter have higher insecticidal activities. There are two or three chiral C in the insecticides, so it is possible to have two~four pairs of enantiomeric isomers. The insecticidal activities are different in enantiomeric isomers.Separation of trans- and m-DCCA was performed by using their different dissolubility and pK3 value, satisfactory results were obtained with yield of 83.7% for trans- DCCA and 88.9% for cis -DCCA. The DCCA, cis-DCCA and trans-DCCA, reacted with S(-)-ct -phenylethyl amine to form their amidates, which were purified by TLC, then determinedby HPLC with a reference of the amidates of DCCA. The racemic purity of cis- and trans-DCCA was 91.4% and 93.0%, respectively.Enantiomeric isomers of (?-N-(2,6-xylyl)-alanine, cis- and trans-DCCA, which are key intermediates for preparation of N-acylalanines and DCCA pesticides, were separated by using ?-)- a -phenylethyl amine as a derivatization reagent. The racemic and enantiomeric isomers of cis-DCCA were reacted with ?-)- a -phenylethyl amine to form their amidates, which were purified by TLC, then determined by HPLC with a reference of the amidate of the cis-DCCA. The optical purity of cis-R(+)-and cis-S( -) -DCCA was 93.7% and 81.8%, respectively. Optical purity of trans-DCCA can be analyzed by a similar method.Using a - chloropropionic acid, methanol, 2,6 - dimethylaniline, DCCA and cis-DCCA, a series of N-acylalanines were synthesized. The aim of this dissertation is try to attain some compounds have stereoscopic structure and biological activity.The quantities of twenty-one compounds were analyzed by HPLC, and IR, GC/MS, NMR and elemental analysis verified structures of twenty-one compounds after were purified.The twenty-one compounds were used for general bioactivity screening of insecticidal,fungicidal and herbicidal activities, according to the procedure of SOP. 12 and 14 compounds have insecticidal activities to Culer pipiens, and 2 , 9*, 16 and 19 compounds have insecticidal activities to Mythimna seperata. 4# compound has fungicidal activity to Pyricularia oryzae, 15* compound has fungicidal activity to Fusarium graminearum and 9#, 16* compounds have fungicidal activities to Erysiphe graminis. The twenty-one compounds have no herbicidal activities.The twenty-one compounds were checked through the international journals and patents by Internet, and nineteen of them have not been found be published or patented.