Subject Epicatechin

The synthetic protocol (Scheme 11.2) toward the flavan-3-ol permethylaryl ethers is based upon the transformation of rc7ro-chalcones into 1,3-diarylpropenes. These compounds are then subjected to asymmetric dihydroxylation to give diarylpropan-l,2-diols that are used as chirons for essentially enantiopure flavan-3-ols. The protocol is demonstrated in Scheme 11.2 for the synthesis of the tetra-(9-methyl-3-(9-acetyl derivatives 61a, 61b, 62a, and 62b of (-l-)-catechin (2), (—)-e 7-catechin, (—)-epicatechin (3), and (+)-e 7-epicatechin (4). ... 

Epicatechin is one of the flavonoids in green tea and is present in tea leaves as the aglycone. It has been the subject of additional transport studies in our... 

So, it appears to be very likely that the difference between the earlier study by Das and associates [27] and the 1983 study by Hacked and colleagues [26] is due to different gut microflora in the subject populations. This hypothesis is strengthened by the results in 2000 of Li and coworkers [67], in that study the variation in the levels of epicatechin and epigallocatechin conjugates excreted in the urine varied fourfold between subjects, similarly to results of other reports, but the levels of the valerolactones varied by more than 10 times. 

Multiple doses of chocolate were administered in a crossover study by Wang and coworkers [10]. Subjects consumed chocolate samples containing 27, 53, or 80 mg of epicatechin. The total amount of glucmonide and sulfate conjugates in plasma were reported. Maximal plasma levels and the area under the curve (AUC) increased proportionally after the three doses. The authors also... 

---