Galactosamine Chiral Auxiliary Induced Asymmetric Synthesis Of ¦Á-amino Phosphonic Acid (ester)

α-Aminophosphonic acids have received great attention in organic synthetic chemistry due to their structural analogy to naturalα-amino acids,and therefore have biological importance.In this paper,the synthetic methods and biological activities ofα-amino phosphonates and their derivates were reviewed.In order to find new leading compounds owning potential biological activity,we developed the new synthetic method and stereoselectively synthesized two series ofα-aminphosphinic acids and derivatives with O-pivaloylated D-galactosylamine as the chiral auxiliary. Their structures were confirmed by ¹H NMR,³¹p NMR,¹³C NMR,ESI-MS, elemental analysis and HRMS.Some of the target compounds were recrystallized and there structures were determined by X-ray diffraction analysis.The first series compounds ofβ-N-glycosidic linkagesα-aminophosphonic acid derivatives have been achieved in high yields and high diastereoselectivity via Mannich-type reaction.The reaction was proceeded by using O-pivaloylated galactosylamine as chiral template and boron trifluoride diethyl ether as catalyst in THF.Imines of aromatic and diethyl phosphite were converted to N-galactosylα-aminoalkylphosphonate,giving ratios of diastereomers higher than 19:1.This procedure provides rapid access to biologically important galactosylα-aminophosphonic acid derivatives.The primary structure S was determined by X-ray diffraction analysis.The second series compounds ofα-Amino(phenyl)methyl(phenyl)Phosphinic Acids have been achieved with high yield and high enantioselectivity.The reaction was performed by using O-pivaloylated galactosylamine as a chiral template and SnCl₄ as catalyst in THF.Imines of aromatic and ethyl phenylphosphinate were converted to(S)-α-[(O-pivaloylhexapyranosyl)amino]benzylphosphonates via Mannich-type reaction,giving ratios of diastereomers higher than 12:1.This procedure provides rapid access to biologically important galactosylα-aminophosphonic acids derivatives.(S)-α-Amino(phenyl)methyl(phenyl) Phosphinic acids can be stereoselective synthesized from N-galactosylα-aminoalkylphosphonates.