197714-08-2

Upstream product

• 18162-48-6 tert-butyldimethylsilyl chloride 
• 121840-97-9 (2R,3R)-3-phenyl-butane-1,2-diol 
• 4407-36-7 (2E)-3-phenyl-2-propen-1-ol 
• 104196-23-8 (2S,3S)-2,3-epoxy-3-phenyl-1-propanol 

Downstream Products

• 197714-16-2 (2S,3R)-1-[(tert-butyldimethylsilyl)oxy]-3-phenyl-2-[(p-nitrobenzoyl)oxy]butane 
• 128677-94-1 (2S,3R)-2-azido-3-phenylbutanoic acid 
• 1377321-85-1 (2R,3R)-2-methyl-3-(((2S,3R)-2-((2E,4E)-4-methylhexa-2,4-dienamido)-3-phenylbutanoyl)oxy)butanoic acid 
• 197714-24-2 (2S,3R)-1-[(tert-butyldimethylsilyl)oxy]-3-phenyl-2-(methanesulfonyloxy)butane 
• 197714-29-7 methyl (2R,3R)-2-[(tert-butoxycarbonyl)amino]-3-phenylbutanoate 
• 197714-18-4 methyl (2S,3R)-2-[(tert-butoxycarbonyl)amino]-3-phenylbutanoate 
• 197714-22-0 (2S,3R)-1-[(tert-butyldimethylsilyl)oxy]-3-phenyl-2-butanol 
• 197714-31-1 (2R,3R)-2-[(tert-butoxycarbonyl)amino]-3-phenylbutanol 
• 197714-07-1 methyl (2R,3R)-2-(methanesulfonyloxy)-3-phenylbutanoate 
• 197714-21-9 methyl (2S,3R)-2-(methanesulfonyloxy)-3-phenylbutanoate 
• 197714-26-4 (2S,3R)-3-phenyl-2-(methanesulfonyloxy)-1-butanol 
• 197714-12-8 (2R,3R)-2-(methanesulfonyloxy)-3-phenyl-1-butanol 

Relevant academic research and scientific papers

First Total Synthesis of Jomthonic Acid A 1

A stereoselective total synthesis of jomthonic acid A is described. The key features of the synthetic strategy are a Sharpless asymmetric epoxidation, a Gilmann reagent-induced methylation, a Mitsunobu reaction, a Yamaguchi esterification, and an O -(benzotriazol-1-yl)- N, N, N ′, N ′-tetramethyluronium tetrafluoroborate (TBTU)-mediated amide coupling. Jomthonic acid A is an architecturally rare amino acid containing a β-methylphenylalanine residue and a 4-methyl-(2 E,4 E)-hexa-2,4-dienoate moiety. It shows antidiabetic and antiatherogenic activities when tested against mouse ST-13 preadiopocytes.

A Catalytic Asymmetric Synthesis of N-Boc-β-Methylphenylalanines

An efficient, stereodivergent, and enantioselective synthesis of the syn and anti diastereomers of N-Boc-β-methylphenylalanine has been developed. Starting from enantiomerically pure (2S,3S)-2,3-epoxy-3-phenyl-1-propanol, a three-step sequence, consisting of the oxidation of the primary alcohol up to the carboxyl stage, ring opening of the epoxy acid with Me2CuCNLi2, and esterification of the resulting hydroxy acid with methyl iodide, leads to the hydroxy ester anti-W, which has been converted in a stereodivergent manner into both the (2S,3R) and the (2R,3R) diastereomers of N-Boc-β-methylphenylalanine, syn-1 and anti-1, respectively. Activation of the secondary hydroxy group in anti-10 as a mesylate, followed by nucleophilic displacement with sodium azide, hydrogenolysis with simultaneous protection of the amino group, and saponification with LiOH, affords syn-1. The same reaction sequence applied to syn-10, obtained in turn by Mitsunobu reaction of anti-10 with p-nitrobenzoic acid followed by the hydrolysis of the resulting p-nitrobenzoate, leads to anti-1. Both products have been obtained with ≥99% enantiomeric excess.