A series of sulfonamides (1) has been prepared as inhibitors of interleukin-1β converting enzyme (ICE), also known as caspase 1. These compounds were designed to improve potency by rigidifying the enzyme bound molecule through an intramolecular hydrogen bond. An X-ray crystal structure of a representative member of this series bound to the active site of ICE, confirms the presence of the hydrogen bonding interaction.

AbstractDie hohe Diastereoselektivität der Umsetzung von α‐(1H‐1,2,4‐Triazol‐1‐yl)ketonen (1, 4), α‐Alkoxy‐α‐(1H‐1,2,4‐triazol‐1‐yl)ketonen (7, 13) und entsprechender Imidazolderivate (10) mit Grignard‐Reagenzien wird auf die intermediäre Ausbildung von postulierten Chelatkomplexen 3, 9 zurückgeführt. Dabei können sowohl die Alkoxygruppe als auch der Azolsubstituent als Ligand fungieren. Von 2d und 8d wurde eine Röntgenstrukturanalyse ausgeführt.

The compounds [Os3H2(CO)10] and [Os3(CO)10(MeCN)2] each react with 2-ethenylpyridine (NC5H4CHCH2) with C–H bond cleavage at the terminal carbon atom to give [Os3H(CO)10-(NC5H4CHCH)], (1). An analogous compound [Os3H(CO)9(PMe2Ph)(NC5H4CHCH)], (2), is formed similarly from [Os3H2(CO)9(PMe2Ph)]. Single-crystal X-ray structures of compounds (1) and (2) are reported. In these clusters the metal triangles have opened out with Os–Os–Os angles of 160.0(1) and 160.4(1)° in (1) and (2) respectively. Each of the compounds contains a terminal hydride ligand replaceable by Cl in carbon tetrachloride and has a five-electron donor NC5H4CHCH ligand chelating at a terminal Os atom of the Os3 chain with a η2-alkene co-ordination at the central Os atom. 2-Ethynylpyridine (NC5H4CCH) reacts with [Os3H2(CO)10] to give compound (1) and an isomer in which the alkene is trans rather than cis and in which the 2-pyridyl group is non-co-ordinated.