Cefclidin is a fourth-generation cephalosporin antibiotic effective against a clinical strain of Citrobacter freundii. The affinity of cefclidin for the β-lactamase isolated from these mutants was lower than that of ceftazidime, and the kinetic parameters of enzymatic hydrolysis showed that cefclidin was hydrolyzed more slowly at a low concentration than was ceftazidime. It is suggested that the high activity of cefclidin against strains derepressed for β-lactamase plays a major role in the absence of emergence of resistant mutants.

Cefcanel is a semisynthetic third-generation cephalosporin with antibacterial activity. Cefcanel is active against the species E. coli, K. aerogenes and Proteus mirabilis; H. influenzae and M. catarrhalis has reasonable susceptibility. Cefcanel inhibits 90% of S. aureus strains at 2 µg/ml, irrespective of the presence of a β-lactamase. Cefcanel binds to and inactivates penicillin-binding proteins (PBPs) located on the inner membrane of the bacterial cell wall. PBPs are enzymes involved in the terminal stages of assembling the bacterial cell wall and in reshaping the cell wall during growth and division. Inactivation of PBPs interferes with the cross-linkage of peptidoglycan chains necessary for bacterial cell wall strength and rigidity. This results in the weakening of the bacterial cell wall and causes cell lysis.

Fasobegron is an agonist of β3-adrenoreceptor.

Fumoxicillin was developed as an antibacterial agent that binds to penicillin-binding protein and inhibits the bacterial cell wall biosynthesis. Information about the current development of this compound is not available.

Tazolol is a selective myocardial beta-blocking agent. Experiments on dogs have shown that this compound could be useful in patients with heart failure due to coronary artery disease. However, information about the current use of tazolol is not available.

Levopropylcillin – is a penicillin derivative, L-enantiomer of antibiotic Propicillin. Levopropylcillin properties are similar to benzylpenicillin particularly used in streptococcal infections, not resistant to penicillinase. Levopropylcillin is acid resistant and can be used orally as the potassium salt.

Adaprolol is a beta-adrenergic antagonist that is being developed as a topical agent to treat glaucoma. Adaprolol demonstrated a safer cardiovascular profile, especially in the population over 70 years old. It was in Phase II clinical trials for the treatment of glaucoma. This research has been discontinued.

Milveterol (also known as GSK159797) was developed as a longer-acting beta2 adrenoceptor agonist for the treatment of respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD). Milveterol completed phase II clinical trials for asthmatic subjects. However further development of the drug was discontinued.

Pirepolol is the beta-adrenergic blocking agent. It was developed as an antihypertensive agent.

Ronactolol is an aminopropanol derivative and a beta-adrenergic receptor antagonist. This compound has been withdrawn from development.