Structure of a nanobody-stabilized active state of the β(2) adrenoceptor.

G protein coupled receptors (GPCRs) exhibit a spectrum of functional behaviours in response to natural and synthetic ligands. Recent crystal structures provide insights into inactive states of several GPCRs. Efforts to obtain an agonist-bound active-state GPCR structure have proven difficult due to the inherent instability of this state in the absence of a G protein.

Discovery of olodaterol, a novel inhaled beta2-adrenoceptor agonist with a 24 h bronchodilatory efficacy.

Compound 4p was identified from a series of 6-hydroxy-4H-benzo[1,4]oxazin-3-ones as potent agonist of the human beta2-adrenoceptor with a high beta1/beta2-selectivity. A complete reversal of acetylcholine-induced bronchoconstriction which lasted over the whole study period of 5h was demonstrated for 4p in a guinea pig in vivo model without any signs of cardiovascular effects up to 10-fold above the first dose reaching 100% bronchoprotection. The enantiomerically pure (R)-form of 4p exerted a bronchodilatory efficacy over 24 h in dogs and guinea pigs in the absence of systemic pharmacodynamic effects.

Use of 5-hydroxy-4H-benzo[1,4]oxazin-3-ones as beta2-adrenoceptor agonists.

Novel beta(2)-agonists with a 5-hydroxy-4H-benzo[1,4]oxazin-3-one moiety as head group are described. Systematic chemical variations at the phenethylamine residue of these compounds lead to the discovery of compound 6m as potent, full agonist of the beta(2)-adrenoceptor with a high beta(1)/beta(2)-selectivity. Molecular modeling revealed an interaction between the carboxylic acid group of 6m and a lysine residue (K305) of the beta(2)-receptor as putative explanation for the high observed selectivity.

Studies towards topical selective beta2-adrenoceptor agonists with a long duration of action.

Beta2-adrenoceptor agonists with basic and acidic groups attached via an alkyl linker to the phenyl ethanolamine core were prepared and investigated in vitro and in vivo. The compounds exhibited a high potency in a functional cellular assay and a bronchoprotective effect in a guinea pig model which lasted over the complete study period of 5h.

A convergent three-component total synthesis of the powerful immunosuppressant (-)-sanglifehrin a.

The potent immunosuppressive agent (-)-sanglifehrin A (5), initially discovered in a soil sample from Malawi, has been synthesized in a highly convergent and stereocontrolled manner. The enantioselective approach relies on initial construction of the iodovinyl carboxylic acid 14, which is coupled to tripeptide 59 in advance of a key macrolactonization step that generates 61a. An alternative protocol that involves the linkage of 14 to 46 for possible construction of the large ring failed due to an inability to bring about a corresponding macrolactamization maneuver.