188446-23-3

Upstream product

• 4397-53-9 p-benzyloxybenzaldehyde 
• 109838-85-9 (2R)-2,5-dihydro-2-isopropyl-3,6-dimethoxypyrazine 

Downstream Products

• 188446-25-5 methyl (2S,3S)-2-amino-3-(4-(benzyloxy)phenyl)-3-hydroxypropanoate 
• 864954-42-7 (2R,5S,αS)-5-[4'-benzyloxy-α-methoxy]benzyl-2,5-dihydro-3,6-dimethoxy-2-isopropylpyrazine 
• 700816-79-1 (2S,3S)-2-amino-3-(4-hydroxyphenyl)-3-methoxypropanoic acid 
• 864954-43-8 (S)-O-benzyl-β-methoxy-L-tyrosine methyl ester 
• 865062-12-0 (S)-O-benzyl-β-methoxy-L-tyrosine allyl ester 
• 188446-49-3 (2S,3S)-2-Amino-3-(tert-butyl-dimethyl-silanyloxy)-3-(4-fluoro-3-nitro-phenyl)-propionic acid methyl ester 
• 188446-29-9 methyl (2S,3S)-2-amino-3-(4-(benzyloxy)phenyl)-3-((tert-butyldimethylsilyl)oxy)propanoate 
• 188446-33-5 (2S,3S)-2-(tert-Butoxycarbonyl-methyl-amino)-3-(tert-butyl-dimethyl-silanyloxy)-3-(4-hydroxy-phenyl)-propionic acid 
• 188446-31-3 (2S,3S)-3-(4-Benzyloxy-phenyl)-2-tert-butoxycarbonylamino-3-(tert-butyl-dimethyl-silanyloxy)-propionic acid 
• 188446-50-6 (2S,3S)-2-tert-Butoxycarbonylamino-3-(tert-butyl-dimethyl-silanyloxy)-3-(4-fluoro-3-nitro-phenyl)-propionic acid methyl ester 
• 188446-30-2 (2S,3S)-3-(4-Benzyloxy-phenyl)-2-tert-butoxycarbonylamino-3-(tert-butyl-dimethyl-silanyloxy)-propionic acid methyl ester 
• 188446-32-4 (2S,3S)-3-(4-Benzyloxy-phenyl)-2-(tert-butoxycarbonyl-methyl-amino)-3-(tert-butyl-dimethyl-silanyloxy)-propionic acid 
• 188446-34-6 (2S,3S)-2-(tert-Butoxycarbonyl-methyl-amino)-3-(tert-butyl-dimethyl-silanyloxy)-3-(4-hydroxy-phenyl)-propionic acid pentafluorophenyl ester 
• 188446-35-7 (S)-2-[(2S,3S)-2-(tert-Butoxycarbonyl-methyl-amino)-3-(tert-butyl-dimethyl-silanyloxy)-3-(4-hydroxy-phenyl)-propionylamino]-3-(3-fluoro-4-nitro-phenyl)-propionic acid methyl ester 

Relevant academic research and scientific papers

A Synthetic Route to β-Hydroxytyrosine-Derived Tetramic Acids: Total Synthesis of the Fungal Metabolite F-14329

3-Acyltetramic acids derived from β-hydroxytyrosine are synthetically challenging. The first route to this structural motif, based upon a condensation between a Meldrum's acid conjugate bearing the acyl side chain, and a β-hydroxytyrosinate, N-protected by an ortho-nitrobenzyl group is presented. This group enables the Dieckmann cyclization of the resulting N-(β-ketoacyl)amino ester, after which it can be removed photolytically without compromising the delicate 3′-hydroxy group. This strategy was applied to the first total synthesis of the fungal metabolite F-14329 (1).

Complete stereochemistry of neamphamide A and absolute configuration of the β-methoxytyrosine residue in papuamide B

The absolute stereochemistry of the three unresolved structural components in neamphamide A (1) was determined to be (R)-β-methoxy-L-tyrosine, (2R,3A,4S)-4-amino-7-guanidino-2,3-dihydroxy-heptanoic acid, and (2R,3R,4R)-3-hydroxy-2,4,6-trimethylheptanoic acid. Stereochemical assignments were made by chemical degradation of 1, derivatization of the resulting products, and then spectroscopic and chromatographic comparison of the derivatives with synthetically prepared standards. Using the same analytical protocol developed for 1, the β-methoxytyrosine residue in papuamide B (2) was found to be (R)-β-methoxy-D-tyrosine. This represents a rare example of divergent stereochemistry in an unusual amino acid residue that is present in two closely related classes of peptides.

Synthesis of (9R,12S)- and (9S,12S)-cycloisodityrosine and their N-methyl derivatives

Full details of the synthesis of (9R,12S)- and (9S,12S)-cycloisodityrosine and their N-methyl derivatives are detailed based on an intramolecular nucleophilic aromatic substitution reaction for formation of the key biaryl ether with 14-membered ring macrocyclization. Their comparison with prior samples and the documentation of a facile C9 epimerization within the natural 9S series are described.