Abstract
We report here a practical and efficient synthesis of α-aminophosphonic acid incorporated into 1,2,3,4-tetrahydroquinoline and 1,2,3,4-tetrahydroisoquinoline heterocycles, which could be considered to be conformationally constrained analogues of pipecolic acid. The principal contribution of this synthesis is the introduction of the phosphonate group in the N-acyliminium ion intermediates, obtained from activation of the quinoline and isoquinoline heterocycles or from the appropriate δ-lactam with benzyl chloroformate. Finally, the hydrolysis of phosphonate moiety with simultaneous cleavage of the carbamate afforded the target compounds.
Highlights
There is a continuously growing interest in the development of new peptidomimetics, compounds that mimic the bioactive conformation and action of therapeutic peptides while possessing greater bioavailability and stability and less undesirable effects
[26,27,28,41,42,43], we report the practical and efficient synthesis of α-aminophosphonic acids we report the practical and efficient synthesis of α-aminophosphonic acids incorporating incorporating 1,2,3,4-tetrahydroquinoline 4, and 1,2,3,4-tetrahydroisoquinoline rings 5 and 6, which
Synthesis of 1,2,3,4-tetrahydroisoquinoline-1-phosphonic we focused on the preparationof of 1,2,3,4-tetrahydroisoquinoline-3-phosphonic
Summary
There is a continuously growing interest in the development of new peptidomimetics, compounds that mimic the bioactive conformation and action of therapeutic peptides while possessing greater bioavailability and stability and less undesirable effects. Some of the most important molecules are the 1,2,3,4-tetrahydroquinoline-2-carboxylic acid 1 [3,4] and 1,2,3,4-tetrahydroisoquinoline-1-carboxylic acid 2 [5,6], which are conformationally constrained analogues of unnatural pipecolic acid, and 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (Tic) 3 [7,8], which is considered a conformationally constrained analogue of phenylalanine (Phe) These compounds are important unnatural α-amino acids, and they are used as key intermediates in organic synthesis for the preparation of biologically active compounds. The α-aminoalkylphosphonic acids are probably the most important analogues of the α-amino acids, obtained by isosteric substitution of the planar and less bulky carboxylic acid (CO2 H) by a tetrahedral phosphonic acid functionality (PO3 H2 ) This class of compounds is currently attracting interest in organic and medicinal chemistry, due to their important biological and pharmacological properties [9,10,11,12]. The great importance of this type of compound has prompted organic chemists to report numerous procedures for their racemic or stereoselective synthesis [13,14,15,16,17,18], principally using the diastereoselective and enantioselective
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
