250249-07-1

Upstream product

• 250249-06-0 2-[2-tert-butoxycarbonylamino-2-(4-methoxy-phenyl)-acetylamino]-3-(tert-butyl-dimethyl-silanyloxy)-3-(4-hydroxy-phenyl)-propionic acid ethyl ester 
• 4397-53-9 p-benzyloxybenzaldehyde 
• 156407-78-2 (R)-tert-butoxycarbonylamino-[4-methoxy-phenyl]-acetic acid 
• 37763-23-8 D-2-p-hydroxyphenylglycine methyl ester 
• 123-08-0 4-hydroxy-benzaldehyde 
• 143323-49-3 (R)-methyl 2-((tert-butoxycarbonyl)amino)-2-(4-hydroxyphenyl)acetate 
• 104315-07-3 (E)-ethyl 3-(4-(benzyloxy)phenyl)acrylate 
• 218912-05-1 (2S,3R)-2-Benzyloxycarbonylamino-3-(4-benzyloxy-phenyl)-3-(tert-butyl-dimethyl-silanyloxy)-propionic acid ethyl ester 
• 218912-06-2 (2S,3R)-2-Amino-3-(tert-butyl-dimethyl-silanyloxy)-3-(4-hydroxy-phenyl)-propionic acid ethyl ester 
• 193073-85-7 methyl (R)-2-((tert-butoxycarbonyl)amino)-2-(4-methoxyphenyl)acetate 

Downstream Products

• 250249-09-3 (2S,3R)-2-[(R)-2-{(R)-2-tert-Butoxycarbonylamino-2-[3,5-dibromo-4-(pyrrolidin-1-ylazo)-phenyl]-acetylamino}-2-(4-methoxy-phenyl)-acetylamino]-3-(tert-butyl-dimethyl-silanyloxy)-3-(3-chloro-4-hydroxy-phenyl)-propionic acid ethyl ester 
• 250249-08-2 (2S,3R)-2-[(R)-2-Amino-2-(4-methoxy-phenyl)-acetylamino]-3-(tert-butyl-dimethyl-silanyloxy)-3-(3-chloro-4-hydroxy-phenyl)-propionic acid ethyl ester 

Relevant academic research and scientific papers

Bishomoaromatic 1,2,4-triboracyclopentane dianions: Strong three-center, two-electron bonds between three boron atoms

Much greater than the bishomoaromaticity for the archetype 1 of all bishomoarenes is that of 1,2,4-triboracyclopentane dianions 2, although the skeletons of 2 are isoelectronic with that of the experimentally unknown monocyclic prototype 3. Donor substitu

Total synthesis of vancomycin - Part 2: Retrosynthetic analysis, synthesis of amino acid building blocks and strategy evaluations

Retrosynthetic analysis of vancomycin (1) defined vancomycin's aglycon (2) and protected triazene 3 (Figure 1) as advanced intermediates for an eventual total synthesis. Sequential assembly of 3 as shown in Figure 2 (strategy I) and Figure 3 (strategy II) led to amino acid building blocks 8-10 and 12-15, respectively, representing vancomycin's amino acids AA-1 to AA-7. These amino acid fragments were constructed by stereoselective routes and the two synthetic strategies were tested for feasibility. Strategy I, postulating construction of the vancomycin main framework in the order of D-O-E→D-O-E/C-O-D→D-O-E/C-O-D/A-B, suffered from serious epimerization problems at the AA-4 stereocenter; while strategy II, involving the sequence C-O-D→C-O-D/AB→C-O-D/AB/D-O-E proved viable. These findings set the stage for the final drive towards vancomycin's aglycon (2) and vancomycin (1).