Chiral Br (?) Nsted Acid Catalyzed Asymmetric Synthesis And Biological Activity Of, In Fluorine-containing ¦Á-amino Phosphonates

α-Aminophosphonic acids, bioisoters of natural amine acids, have been found to exhibit a wide range of biological activities. Someα-aminophosphonic acid derivatives are used as herbicides, fungicides, plant growth regulators, anti-cancer agents and have antiviral properties. Since stereochemistry at theα-carbon atom plays an important role in the biological activity of the molecule, the synthesis of chiralα-aminophosphonates has been a focus of considerable attention in synthetic organic chemistry, pesticide chemistry as well as in modern pharmaceutical chemistry.Keeping these considerations in mind, in order to find potent environmental friendly and non toxic antiviral agents against tobacco mosaic virus (TMV), fourteen new fluorine containing bioactive chiralα-aminophosphonates in high enantiomeric purity were asymmetrically synthesized using chiral Bronsted acid organocatalyst derived from (R)-binaphthol(BINOL) in a typical hydrophosphonylation reaction of aldimines obtained from cinnamaldehyde and fluorinated aromatic amine with dialkyl phosphites. The synthetic methods and optimization of reaction conditions are discussed in the thesis. The compounds were characterized by IR, elemental analysis and ¹H, ¹³C, ³¹P and ¹⁹F NMR spectral data. The enantiomeric excess (65.2-90.6%) was determined on a chiral HPLC column. The chiral catalyst (R)-3,3'-[3,5-bis(triflu oromethyl)phenyl]₂-1,1'-binaphthol phosphate was synthesized from (R)-BINOL via a five step synthetic sequence involving etherification, boronation, Suzuki coupling, demethylation and phosphorylation under strictly inert atmosphere.A half-leaf method was used to determine in vivo efficacy of the title products against TMV, the results of bioassay showed that all the compounds exhibited certain anti-TMV activity at a concentration of 500μg/mL, especially, compound 2g exhibited a curative effect up to 52.2% against TMV, which is almost similar to that obtained with standard Ningnanmycin (59.96%). The protective activity of compound 2f was found to be 49.62%, inactivation activities of 2a, 2g and 2h were 82.50%,80.21%,80.13% respectively. Under similar condition, the protective and inactivation activities of Ningnanmycin which served as reference antiviral agent were 68.27% and 95.27% respectively at 500μg/mL.