δ-Carbolines and their ring-opened analogs: Synthesis and evaluation against fungal and bacterial opportunistic pathogens

► N-Substituted δ-carbolines have been identified as novel anti-opportunistic infection agents and several synthetic analogs show potency over 100-fold that of the original natural product. ► Toxicity has also been attenuated several fold over the parent compounds the introduction of omega-cyclohexylpentyl moiety. ► Overall, the optimized compounds are fungicidal and bactericidal in contrast to the parent compounds which are only fungistatic and bacteriostatic.