252273-54-4

Upstream product

• 90-02-8 salicylaldehyde 
• 75-03-6 ethyl iodide 
• 179618-33-8 ethyl (2E,4S)-4-{[(tert-butyl)(dimethyl)silyl]oxy}-4-phenylbut-2-enoate 
• 179618-34-9 ethyl (2S,3S,4R)-4-{[(tert-butyl)(dimethyl)silyl]oxy}-2,3-dihydroxy-4-phenylbutanoate 
• 187931-99-3 ethyl (4S,5S)-5-[(R)-{[(tert-butyl)(dimethyl)silyl]oxy}(phenyl)methyl]-2,2-dimethyl-1,3-dioxolane-4-carboxylate 

Downstream Products

• 252273-55-5 ethyl (2S,3R,4S)-2,3-isopropylidenedioxy-4-(4-nitrobenzyloxy)-4-phenylbutanoate 
• 164668-41-1 (5S)-5-[(1S,2R,3S)-1,2,3-trihydroxy-3-phenylpropyl]furan-2(5H)-one 
• 147527-10-4 (5S,6R)-6-[(1R,2S)-1,2-dihydroxy-2-phenylethyl]-5-hydroxy-5,6-dihydro-2H-pyran-2-one 
• 252273-59-9 (R)-2-Benzenesulfonyl-1-{(4R,5S)-5-[(S)-(tert-butyl-diphenyl-silanyloxy)-phenyl-methyl]-2,2-dimethyl-[1,3]dioxolan-4-yl}-4,4,4-trimethoxy-butan-1-ol 
• 252273-62-4 (2R,3S,4S)-1-(t-butyldiphenylsilyloxy)-2,3-isopropylidenedioxy-4-phenyl-1-trifluoromethanesulfonyloxybutane 
• 252273-61-3 (1S,2S,3R)-1-(t-butyldiphenylsilyloxy)-2,3-isopropylidenedioxy-1-phenylbutan-4-ol 
• 214678-61-2 (R)-4-Benzenesulfonyl-6-((1R,2S)-1,2-dihydroxy-2-phenyl-ethyl)-tetrahydro-pyran-2-one 
• 252273-56-6 ethyl (2S,3R,4S)-4-hydroxy-2,3-isopropylidenedioxy-4-phenylbutanoate 
• 252273-58-8 trimethyl [5S,6S,7S]-7-(t-butyldiphenylsilyloxy)-5,6-isopropylidenedioxy-4-oxo-7-phenyl-3-phenylsulfonylorthoheptanoate 
• 252273-57-7 ethyl (2S,3R,4S)-4-(t-butyldiphenylsilyloxy)-2,3-isopropylidenedioxy-4-phenylbutanoate 

Relevant academic research and scientific papers

Et3B/Et2AlCl/O2-Mediated Radical Coupling Reaction between α-Alkoxyacyl Tellurides and 2-Hydroxybenzaldehyde Derivatives

A newly devised radical-based strategy enabled coupling between multiply oxygenated α-alkoxyacyl tellurides and 2-hydroxybenzaldehyde derivatives. A reagent combination of Et3B, Et2AlCl, and O2 promoted the formation of the α-alkoxy carbon radical from the α-alkoxyacyl telluride and the addition of the radical to the carbonyl group of 2-hydroxybenzaldehyde. The reaction chemo- and stereoselectively forged the hindered C?C bond between two oxygen-functionalized carbons at ambient temperature. The method was applied to the preparation of 12 coupling adducts with three to six contiguous stereocenters and to the concise synthesis of an antitumor compound, LLY-283.

Total synthesis of antitumor Goniothalamus styryllactones

Synthesis of eight enantiopure styryllactones has been achieved from a common precursor: ethyl (2S, 3S, 4R)-4-(t-butyldimethylsilyloxy)-2,3- isopropylidenedioxy-4-phenylbutanoate 16, prepared in five steps and 65% yield from (R)-mandelic acid. Key elements for the synthesis of goniofufurone 3, goniopypyrone 4, goniobutenolides A and B (5, 6) and 7-epi-goniofufurone 7 were the introduction of the Z-acrylate moiety by a Julia coupling between 16 or its epimer in benzylic position and methyl 3-phenylsulfonyl orthopropionate 11 followed by a highly diastereoselective reduction of the resulting β-keto sulfone which sets up the last of the four contiguous asymmetric center. In the case of styryllactones 4 and 7, prior to the Julia coupling, the benzyl sterocenter of 16 was efficiently inverted by a Mitsunobu reaction. Goniodiol 1 and 9-deoxygoniopypyrone 2 were synthesized via an efficient coupling between the primary triflate derived from the common intermediate 16 or its epimer and Ghosez's sulfone 11 followed by lactonization and PhSO2H elimination. Goniodiol 1 has been efficiently converted to another styryllactone: isogoniothalamin epoxide 41. Addition of the Ghosez's sulfone to an epoxide derived from the enantiomer of 16 allowed a short synthesis of 8-epi-9-deoxygoniopypyrone 8, thereby establishing that its structure is the following: (1R, 5R, 7S, 8S)-8-hydroxy-7-phenyl-2,6- dioxabicyclo[3.3.1] nonan-3-one.

Total synthesis of antitumor agents, (+)-goniopypyrone and (+)-7-epi-goniofufurone

Synthesis of enantiopure (+)-7-epi-goniofufurone 1 and (+)-goniopypyrone 2 has been achieved from C-4 carbon chain chiron 3, readily available from (R)-mandelic acid.