129778-99-0

Basic information

• Product Name: Boc-L-Tyr(Bu^t)-OCO₂Buⁱ
• Synonyms: Boc-L-Tyr(Bu^t)-OCO₂Buⁱ
• CAS NO: 129778-99-0
• Molecular Weight: 437.533
• Mol File: 129778-99-0.mol

Chemical Properties

• CAS DataBase Reference: Boc-L-Tyr(Bu^t)-OCO₂Buⁱ(CAS DataBase Reference)
• NIST Chemistry Reference: Boc-L-Tyr(Bu^t)-OCO₂Buⁱ(129778-99-0)
• EPA Substance Registry System: Boc-L-Tyr(Bu^t)-OCO₂Buⁱ(129778-99-0)

Safety Data

• Hazardous Substances Data: 129778-99-0(Hazardous Substances Data)

Upstream product

• 47375-34-8 Boc-Tyr(t-Bu)-OH 
• 543-27-1 isobutyl chloroformate 

Downstream Products

• 155919-52-1 Boc-Tyr(tBu)-D-Orn-2-Nal-Pro-Gly-OH 
• 155919-51-0 Boc-Tyr(tBu)-D-Orn-2-Nal-D-Pro-Gly-OH 
• 155919-53-2 Boc-Tyr(tBu)-c<-D-Orn-2-Nal-D-Pro-Gly-> 
• 155919-61-2 Boc-Tyr(tBu)-D-Lys-2-Nal-D-Pro-Gly-OH 
• 155919-71-4 Boc-Tyr(tBu)-D-Orn-Trp-D-Pro-Gly-OH 
• 155919-58-7 Boc-Tyr(tBu)-D-Orn-1-Nal-D-Pro-Gly-OH 
• 155943-05-8 Boc-Tyr(tBu)-D-A₂bu-2-Nal-D-Pro-Gly-OH 
• 155919-62-3 Boc-Tyr(tBu)-c<-D-Lys-2-Nal-D-Pro-Gly-> 
• 155919-72-5 Boc-Tyr(tBu)-c<-D-Orn-Trp-D-Pro-Gly-> 
• 155919-59-8 Boc-Tyr(tBu)-c<-D-Orn-1-Nal-D-Pro-Gly-> 
• 155919-67-8 Boc-Tyr(tBu)-c<-D-A₂bu-2-Nal-D-Pro-Gly-> 
• 155919-76-9 Boc-Tyr(tBu)-D-Orn-2-Nal-D-Pro-OH 
• 509077-59-2 methyl ambo-N-{N-[(benzyloxy)carbonyl]-O-tert-butyltyrosinyl}-(difluoromethyl)alaninate 
• 155919-50-9 Boc-Tyr(tBu)-D-Orn(Z)-2-Nal-Pro-Gly-ONb 

Relevant articles and documents

Peptide synthesis with α-(difluoromethyl)-substituted α-amino acids

Methodology for the incorporation of α-(difluoromethyl)-substituted α-amino acids into N- and C-terminal positions of dipeptides as well as into position 2 of tri- and tetrapeptides is described.

Cyclic β-casomorphin analogues with mixed μ agonist/δ antagonist properties: Synthesis, pharmacological characterization, and conformational aspects

Analogues of the potent and moderately μ-opioid-receptor-selective cyclic β-casomorphin-5 derivative H-Tyr-c[-D-Orn-Phe-D-Pro-Gly-] (2) were prepared by conventional solution synthesis. Replacement of the Phe3 residue by 2- naphthylalanine (2-Nal) led to a peptide (4) with high affinity for both μ and δ opioid receptors. This compound turned out to be an agonist in the μ- receptor-representative guinea pig ileum (GPI) assay but a moderately potent antagonist against various δ agonists in the δ-receptor-representative mouse vas deferens (MVD) assay. It thus represents the first known cyclic opioid peptide analogue with mixed μ agonist/δ antagonist properties. Interestingly, replacement of 2-Nal3 in compound 4 with 1-naphthylalanine (1-Nal) resulted in an analogue (5) showing high affinity for μ receptors and a full agonist effect in the MVD assay that was mediated by both μ and δ receptors. Substitution of Trp for Phe3 in 2 (compound 8) was well tolerated at both receptors and led to an analogue with agonist activity in both the GPI and MVD assays. Variation of the peptide ring size in 4 was achieved by substitution of D-Orn2 with D-Lys (compound 6) or D-2,4- diaminobutyric acid (compound 7). Analogue 6 was also a mixed μ agonist/δ antagonist with somewhat lower potency than 4, whereas compound 7 displayed μ agonist and partial δ agonist properties. Further reduction of the peptide ring size, as achieved by deletion of the Gly5 residue, produced a compound (9) which was a full agonist in both bioassays. Conformational analysis of analogues 2, 4, and 5 by 1H NMR spectroscopy and molecular mechanics studies suggested that the overall conformation of parent compound 2 and the 2-Nal-containing peptide 4 was similar, while the side-chain orientation of 1-Nal in peptide 5 was different. These results suggest that the δ antagonist properties of analogue 4 may not be due to a difference in its overall conformation as compared to the agonist 2 but may be a direct effect of the 2-naphthyl moiety per se preventing proper alignment of the peptide for receptor activation.