Diagnostic utility of oxidative damage markers for early rheumatoid arthritis in non-smokers and negative anti-CCP patients.

Background: Besides the development of new markers and diagnostic criteria for rheumatoid arthritis (RA), many patients are still diagnosed after several years of symptoms. Oxidative stress markers are already increased at an early stage of RA. Our aim was to evaluate the additional diagnostic value of these markers.

Remote hydroxylation of methyl groups by regioselective cyclopalladation. Partial synthesis of hyptatic acid-A.

Hyptatic acid-A (32), a 2alpha,3beta,24-trihydroxyolean-12-en-28-oic acid, previously isolated from Hyptis capitata, was obtained from maslinic acid (2). The regioselective cyclopalladation of the axial methyl group on C-4 of maslinic acid afforded the C-24 hydroxymethylene group due to the presence of a C-2-OR substituent. Nevertheless, hederagenin (7) (23-hydroxy derivative) was formed when this oxygenated group was not present.

Epoxides, cyclic sulfites, and sulfate from natural pentacyclic triterpenoids: theoretical calculations and chemical transformations.

Several triterpenic derivatives, with the A-ring functionalized, were semisynthesized from oleanolic and maslinic acids. The reactivities of sulfites, sulfate, and epoxides in these triterpene compounds were investigated under different reaction conditions. Moreover, contracted A-ring triterpenes (five-membered rings) were obtained, by different treatments of the sulfate 7.

Regioselective enzymatic acylations of polyhydroxylated eudesmanes: semisynthesis, theoretical calculations, and biotransformation of cyclic sulfites.

Different lipase enzymes have been tested in order to perform regioselective acetylations on the eudesmane tetrol from vulgarin. High yields (95%) of 1,12-diacetoxy derivative (4) were achieved in 1 h with Candida antarctica lipase (CAL). However, only the 12-acetyl derivative (6) was obtained in similar yield with Mucor miehei (MML) or Candida cylindracea (CCL) lipases.