Diterpenoid sweeteners. Synthesis and sensory evaluation of stevioside analogs nondegradable to steviol

Abstract

A new series of methylase inhibitors has been designed in which the nucleophilic methyl acceptor is attached to the adenosine and/or homocysteine fragments of the methyl donor, S-adenosyhnethionine, to form a "multisubstrate adduct". In the present case, catecholamine analogues attached through a phenethyl sulfide linkage to 5'-thioadenosine or homocysteine have been synthesized, together with the corresponding methylsulfonium salts. These compounds were assayed as inhibitors of catechol O-methyltransferase, and the adenosylsulfonium salts (4) were found to be inhibitors of the enzyme.

Occurrence, Biological Activities and Synthesis of Kaurane Diterpenes and their Glycosides

“…After previous observation that the glycosidic portions of stevioside (78) and rebaudioside (82), linked to the C-19 position of the kaurane skeleton, are not involved in essential interactions with the receptors of the gustative cells, DuBois and collaborators [160,161] proposed the synthesis of analogous glycosides by substitution of the glycosidic portions for other groups with similar polarities, without the loss of the sweetening properties. As result, these researchers observed that the increase of the hydrophilic character of the group at C-19 caused the reduction of the bitter taste, which is characteristic of 78 and 82, leading to the synthesis of products that did not produce any such bitterness.…”

Regioselective Enzyme‐Mediated Glycosylation of Natural Polyhydroxy Compounds. Part 1. Galactosylation of stevioside and steviolbioside

“…The relative sweetness, evaluated by a professional human sensory panel [16], was nearly x 200 with respect to sucrose (stevioside is x 160). The quality of taste was also significantly improved, with a decrease of aftertaste and increase of deliciousness.…”

Photostability of Rebaudioside A and Stevioside in Beverages

“…Included among these stability studies on 1 were evaluations as dry powder, evaluations in model beverages and in buffers over a range of temperatures and pH values, and evaluations for photostability. In addition to our stability study work on 1, we have also (1) developed methods for purification, (2) conducted sensory studies, (3) identified impurities present in both the raw stevia leaf extract as well as in the purified material, (4) determined degradation pathways, and (5) carried out multiple preclinical and clinical safety assessment studies (4).…”