الفهرس 
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Abstract
Several years ago Einhorn and his coworkers introduced the reaction of
’Boc-Ncprotected iminodiacetic acid diesters with various electrophiles to
give the symmetrically disubstituted compounds. Later Boger et al
described a simple, versatile, and general approach to solution phase
syntheses according to the combinatorial approach. This approach was
illustrated employing the synthesis of IDA diamide libraries with a 2-fold
dimerization to convert the monomers first to dimers and then to tetramers.
More recently, liquid phase methods have been developed to provide a
novel series of iminodiacetic acid derivatives targeting the integrin
receptors.
It seemed of interest to study the behavior of N-protected
iminodiacetic acid during the preactivation step and the coupling with
different amino acid derivatives according to the methods of solution and
solid phase synthesis.
For this reason N-protected iminodiacetic acids (Z-IDA 161, Boc-
IDA 148, Fmoc-IDA 162 and Bsmoc-IDA 163) have been synthesized by
two techniques: a) via chloroformate derivatives or b) via the Bolin
technique. Appropriate materials were identified by IR, IH-NMR and
elemental analysis.
Also several coupling reagents were examined. These included
TCFH 158, TFFH 159, HA TU 139, HBTU 118 and HSTU 160, which were
synthesized from tetramethylurea with POCl3 to yield first the dichloro salt.
Subsequently by anion exchange TCFH was obtained and subsequent
treatment of this compound with KF at 60°C or HOBt, HOAt or KOSu at 0
°C gave the desired coupling reagents TFFH 159, HBTU 118, HATU 139
or HSTU 160 respectively.