In vivo knot scoring model for a multifilament suture.

Background: A surgical knot is the key feature to assure appropriate wound support while combining tissue edges. Little evidence is available on the in vivo behavior of knots and the evaluation of knots in the living tissue. This study introduces a knot score model, which is defined by microscopic evaluation and the loop-holding capacity.

Direct episulfidation of alkenes and allenes with elemental sulfur and thiiranes as sulfur sources, catalyzed by molybdenum oxo complexes.

The molybdenum oxo complexes 1a and 1b catalyze efficiently the sulfur transfer to a series of alkenes 4 and allenes 6, for which elemental sulfur, phenylthiirane, or methylthiirane have been employed as sulfur sources to afford the corresponding episulfides 5 and 7. The most effective catalytic episulfidation system to date is the combination of the dithiophosphate-ligated oxo complex 1b and phenylthiirane (Ibeta). This metathesis process is efficient enough to convert usually reluctant alkenes (cyclopentene, cycloheptene, Z-cyclooctene, Z-cyclononene, E-cyclodecene, norbornene, and even bicyclopropylidene) to their episulfides in good yields under mild conditions.

Direct synthesis of isothiocyanates from isonitriles by molybdenum-catalyzed sulfur transfer with elemental sulfur.

The direct molybdenum-catalyzed sulfuration of a variety of isonitriles with elemental sulfur or propene sulfide as sulfur donors affords the corresponding isothiocyanates in good yields and under mild reaction conditions. A catalytic cycle is suggested, in which the molybdenum oxo disulfur complex operates as the active sulfur-transferring species. A novel adduct between the isonitrile and the molybdenum complex has been characterized by X-ray analysis and its association constant determined by UV-vis spectroscopy, but this adduct appears not to be involved in the sulfur-transfer process.