A retrospective study on nested PCR detection of syphilis treponemes in clinical samples: PCR detection contributes to the diagnosis of syphilis in patients with seronegative and serodiscrepant results.

Syphilis, caused by Treponema pallidum ssp. pallidum (TPA), is a persisting global health problem. Although syphilis diagnostics relies mainly on serology, serological tests have some limitations, and it is recommended that the final diagnosis be supported by additional tests.

MLST typing of Treponema pallidum subsp. pallidum in the Czech Republic during 2004-2017: Clinical isolates belonged to 25 allelic profiles and harbored 8 novel allelic variants.

A recently introduced Multilocus Sequence Typing scheme for Treponema pallidum subsp. pallidum was applied to clinical samples collected from 2004 to 2017 from the two largest cities (Prague and Brno) in the Czech Republic. Altogether, a total of 675 samples were tested in this study and 281 of them were found PCR-positive for treponemal DNA and typeable.

Traceless Solid-Phase Synthesis of Ketones via Acid-Labile Enol Ethers: Application in the Synthesis of Natural Products and Derivatives.

In solid-phase organic synthesis, Wang resin is traditionally used for the immobilization of acids, alcohols, phenols, and amines. We report the use of Wang resin for the traceless synthesis of ketones via acid-labile enol ethers. We demonstrate the practicality of this synthetic strategy on the solid-phase synthesis of pyrrolidine-2,4-diones, which represent the core structure of several natural products, including tetramic acid.

In Vivo Dearomatization of the Potent Antituberculosis Agent BTZ043 via Meisenheimer Complex Formation.

Nitrobenzothiazinones are among the most potent antituberculosis agents. Herein, we disclose an unprecedented in vivo reduction process that affords Meisenheimer complexes of the clinical candidates BTZ043 and PBTZ169. The reduction is reversible, occurs in all mammalian species investigated, has a profound influence on the in vivo ADME characteristics, and has considerable implications for the design and implementation of clinical studies.

Ring contraction of 2,5-dihydrobenzo[f][1,2,5]thiadiazepine 1,1-dioxides: access to 4H-benzo[b][1,4]thiazine 1,1-dioxides.

We report an efficient synthesis of 4H-benzo[b][1,4]thiazine 1,1-dioxides via unprecedented ring contraction of 2,5-dihydrobenzo[f][1,2,5]thiadiazepine 1,1-dioxides under mild conditions involving carbon-sulfur bond formation. 2,5-Dihydrobenzo[f][1,2,5]thiadiazepine 1,1-dioxides are easily accessible from commercially available building blocks, including Fmoc-protected amino acids, 2-nitrobenzenesulfonyl chlorides, and bromo ketones. Benzothiazine 1,1-dioxides represent pharmacologically relevant derivatives with biological, medicinal, and industrial applications.