Automated synthesis of sialylated oligosaccharides

• Davide Esposito,
• Mattan Hurevich,
• Bastien Castagner,
• Cheng-Chung Wang and
• Peter H. Seeberger

Beilstein J. Org. Chem. 2012, 8, 1601–1609, doi:10.3762/bjoc.8.183

• the solid-phase synthesis of sialosides we undertook a model solution-phase synthesis of the glycan portion of GM3 ganglioside 16 (Scheme 2). GM3 serves as an important receptor for viral infection [24][25] and contains the common sialyl α-(2→3) galactose motif. The key step en route to compound 16

• carbamates has to be performed manually at the end of an automated sequence. These features make the automated platform very attractive for sialoside synthesis. Based on the encouraging results obtained for the solution-phase synthesis of 16, building blocks 4 and 5 were used for the automated solid-phase

• yield before hydrogenolysis gave the final trisaccharide 16 in 91% yield. The efficiency of the solid-phase and the solution-phase syntheses was compared. The solution-phase synthesis of trisaccharide 16 was completed with an overall yield of 42% (taking into account the preparation of compound 14, 69

Synthesis of trifunctional cyclo-β-tripeptide templates

• Frank Stein,
• Tahir Mehmood,
• Tilman Plass,
• Javid H. Zaidi and
• Ulf Diederichsen

Beilstein J. Org. Chem. 2012, 8, 1576–1583, doi:10.3762/bjoc.8.180

• demanding due to solution-phase synthesis of the β-tripeptides and their final cyclization with low efficiency [8][9]. Moreover, only homofunctionalized cyclic β-tripeptides have been described so far [9][10]. To further investigate and exploit the potential of this class of circular peptides, a synthetic

Polyionic polymers – heterogeneous media for metal nanoparticles as catalyst in Suzuki–Miyaura and Heck–Mizoroki reactions under flow conditions

• Klaas Mennecke and
• Andreas Kirschning

Beilstein J. Org. Chem. 2009, 5, No. 21, doi:10.3762/bjoc.5.21

• processes creates an ideal setup for an automated solution-phase synthesis. Furthermore, this combination of enabling techniques has great potential in the production of fine chemicals [7][8]. In continuation of our efforts in developing immobilization concepts for reagents and catalysts including

The first preparative solution phase synthesis of melanotan II

• Vladimir V. Ryakhovsky,
• Georgy A. Khachiyan,
• Nina F. Kosovova,
• Elena F. Isamiddinova and
• Andrey S. Ivanov

Beilstein J. Org. Chem. 2008, 4, No. 39, doi:10.3762/bjoc.4.39

• stimulating the skin tanning process. In this paper we report the first solution phase synthesis of the title compound. The hexapeptide sequence has been assembled by [(2+2)+1+1] scheme. After removing the orthogonal protection, a carbodiimide mediated lactamization, involving the ε-amino group of lysine and

• accomplished in 12 steps with 2.6% overall yield, affording >90% pure peptide without using preparative chromatography. Keywords: melanotan II; solution phase synthesis; peptide synthesis; Introduction Development of solid phase peptide synthesis methodology [1], recombinant techniques for expressing

• peptide pharmaceuticals are currently produced by chemical synthesis in solution including oxytocin, adrenocorticotropic hormone (ACTH), desmopressin, leuprolide, goserelin, and octreotide [6]. There is no account of a solution phase synthesis of melanotan II. The present paper describes a classical

A practical synthesis of the ¹³C/¹⁵N- labelled tripeptide N-formyl- Met-Leu-Phe, useful as a reference in solid- state NMR spectroscopy

• Sven T. Breitung,
• Jakob J. Lopez,
• Gerd Dürner,
• Clemens Glaubitz,
• Michael W. Göbel and
• Marcel Suhartono

Beilstein J. Org. Chem. 2008, 4, No. 35, doi:10.3762/bjoc.4.35

• cleavage process, EDT and TIS were added as scavengers [23][24]. Conclusion Compared to the solution phase synthesis of peptides, the solid phase synthesis offers a simplified purification of the intermediates. With the improved synthetic protocol based on Fmoc building blocks, where all reaction steps