266318-68-7

Upstream product

• 5754-34-7 2-((4R)-2,2-dimethyl-1,3-dioxolan-4-yl)ethanol 
• 72496-37-8 ((R)-2,2-Dimethyl-[1,3]dioxolan-4-yl)-acetaldehyde 
• 126946-51-8 (R)-ethyl 2-(2,2-dimethyl-1,3-dioxolan-4-yl)acetate 
• 98-59-9 p-toluenesulfonyl chloride 
• 266318-67-6 (R)-4-(2,2-dimethyl[1,3]dioxolan-4-yl)butan-1-ol 

Downstream Products

• 266318-73-4 ethyl (4R,10R)-10,11-dihydroxy-4-methoxymethoxy-11-tosyloxyundecanoate 

Relevant academic research and scientific papers

The first total synthesis of annonacin, the most typical monotetrahydrofuran annonaceous acetogenins.

The first total synthesis of annonacin (1) was achieved by a highly convergent synthetic strategy. All the stereogenic centers were derived from three natural hydroxy acids respectively, except that those at C19 and C20 were produced from a Sharpless AD reaction.

Enantioselective syntheses of monotetrahydrofuran annonaceous acetogenins tonkinecin and annonacin starting from carbohydrates

The total synthesis of two mono-THF acetogenins, tonkinecin (1) and annonacin (2), is reported in full detail. Terminal acetylene 3 prepared from D-glucono-δ-lactone and asymmetric dihydroxylation was employed as a common intermediate for both targets 1 and 2. Pd(0)-catalyzed coupling reaction of 3 with vinyl iodides 4 and 5, the chiral centers of which were taken from D-xylose and S-(-)-ethyl lactate, afforded enyne 26 and 27, respectively. Selective hydrogenation of 26 or 27 with diimide followed by removal of MOM ethers completed the synthesis of 1. A coupling reaction between the lithium derivative of 3 and epoxide 6 in the presence of boron trifluoride etherate gave 42. Both chiral centers in epoxide 6 were taken from L-ascorbic acid. Subsequent catalytic hydrogenation and MOM protection led to 43b. Introduction of the butenolide moiety by aldol condensation of protected S-lactal followed by cleavage of all MOM ethers completed the synthesis of 2.