Adrenoceptors (ARs) belong to the Rhodopsin family of GPCRs (G-Protein Coupled Receptors). These are widely targeted by drugs in the treatment of various diseases. One of the subtypes of ARs, α1ARs regulate sympathetic nervous system with complex effects, either detrimental or protective, on both the heart and brain. Selective drug development for such receptors is hindered by a lack of structural information and the difficulty to stabilise such proteins in detergent or membrane mimetics. The directed evolution stabilisation method, CHESS or Cellular High throughput Encapsulation, Solubilisation and Screening, selects for detergent-stable GPCR mutants which may be more amenable to structural analyses. This study revolves around two such CHESS engineered mutants of α1AAR and α1BAR. We are using these receptors to study their binding properties to a variety of ligands including Adrenaline and α1AAR-selective A-61603, as well as allosteric modulators, benzodiazepines (BZs). BZs have a variety of therapeutic actions including anxiolytic, hypnotic, muscle relaxant, antiepileptic and amnesic, and consequently show poor specificity. Their action on GABAA receptors has been widely studied. Also, they are known to bind and modulate the function of α1AR, but the pharmacology on α1ARs remains largely unclear. This study aims to investigate binding of BZs on α1ARs; eventually, it would be interesting to see if we can find a novel BZ scaffold imparting selectivity towards α1AR. A variety of NMR techniques have been applied including STD-NMR(Saturation-Transfer Difference NMR), transferred NOE and INPHARMA (Interligand Noes for PHARmacophore Mapping), to gain a molecular understanding of how these compounds bind and influence the activity of α1ARs.