Michael additions to double bonds of esters of N-protected (s)-phenylalanyldehydroalanine (X-(s)-Phe-ΔAla-OMe) and its phosphonic acid counterpart (X-(s)-Phe-ΔAla-PO(OEt)₂)

Phosphonopeptides containing free phosphonic groups: recent advances

“…12) indicated that this procedure could be a new mean to produce phosphono peptides containing nontypical side chains (compounds 38 and 39). 54,55 The peptide 37 is also a good entry for compounds 40 by means of addition-elimination reaction upon action of bromine. 55 Upon reaction of 40 with thiophenol functionalized dehydropeptide 41 was obtained.…”

“…54,55 The peptide 37 is also a good entry for compounds 40 by means of addition-elimination reaction upon action of bromine. 55 Upon reaction of 40 with thiophenol functionalized dehydropeptide 41 was obtained. However, the further studies are required to validate general utility of these reactions.…”

Dipeptides of S-Substituted Dehydrocysteine as Artzyme Building Blocks: Synthesis, Complexing Abilities and Antiproliferative Properties

“…Recently we had found that the addition of bromine to compounds 1 and 2 , followed by elimination of the bromine atom by the action of triethylamine provided dehydropeptides 4 and 5 containing ( Z )-β-bromodehydroalanine [ 20 ]. These peptides by being crystalline and stable upon storage had been considered as ideal substrates for addition-elimination reaction and provided readily a series of dehydropeptides (compounds 6 and 7 ; Scheme 1 b).…”

Access to α-Aminophosphonic Acid Derivatives and Phosphonopeptides by [Rh(P–OP)]-Catalyzed Stereoselective Hydrogenation

“…Phosphonodehydropeptides 4 and 5 were prepared according to a previously described synthetic protocol, in which the corresponding amides were used in the condensation step. 10 With the substrates in hand, we proceeded to explore the enantioselective hydrogenation under the standard hydrogenation reaction conditions (1.0 mol % of Rh catalyst, THF, 20 bar H 2 , room temperature, overnight), unless otherwise indicated. The results of this study are shown in Scheme 2.…”

“…Condensation of chloroacetamide with diethyl acetylphosphonate, followed by treatment with aqueous ammonia and subsequent protection of the amino group as the Boc derivative, led to product 3 (Scheme ). Phosphonodehydropeptides 4 and 5 were prepared according to a previously described synthetic protocol, in which the corresponding amides were used in the condensation step …”