Bucladesine is a cyclic nucleotide derivative which mimics the action of endogenous cAMP and is a phosphodiesterase inhibitor. The compound is used in a wide variety of research applications because it mimics cAMP and can induce normal physiological responses when added to cells in experimental conditions. cAMP is only able to elicit minimal responses in these situations. The neurite outgrowth instigated by bucladesine in cell cultures has been shown to be enhanced by nardosinone. Recently, the effect of bucladesine as a cAMP analog has been studied on the pentylenetetrazol-induced seizure in the wild-type mice. The data showed that bucladesine (300nM/mouse) reduced the seizure latency and threshold. In addition they found that combination of bucladesine and pentoxyfillin has additive effect on seizure latency and threshold. Bucladesine is more lipophilic than cAMP and in contrast to cAMP capable of penetrating cell membranes. Bucladesine interferes with different protein kinases which are normally activated by cAMP. Bucladesine has undergone in the past clinical developments as systemic treatment for cardioprotection and as topical treatment to improve wound healing. In Japan, a bucladesine ointment (Actosin® ointment; Daiichi Pharmaceutical Co., Ltd., Tokyo, Japan) was marketed to treat skin ulcers. Clinical studies have shown favourable effects on diabetic foot ulcers or decubitus, but the compound was later withdrawn despite good tolerability. One possible reason for the withdrawal may be the odour of the cream formulation which can be related to the hydrolytic cleavage in aqueous solutions resulting in release of butyric acid.

Amylmetacresol (AMC) is an antiseptic used to treat infections of the mouth and throat. It is used as an active pharmaceutical ingredient in Strepsils, Gorpils and Lorsept throat lozenges. It was shown that the presence of amylmetacresol, dichloro-benzylalcohol and lidocaine block of inward sodium current.

QS-21 is a purified soapbark tree (Quillaja saponaria) extract that enhances the ability of the immune system to respond to vaccine antigens. QS-21 is a promising adjuvant candidate for use in humans due to the ease of purification, its improved safety profile, and its ability to enhance cellular and humoral immunogenicity. The mechanism of action of QS-21 was speculated to be similar to QA, forming complexes with cholesterol that intercalate into the cell membrane lipids. This intercalation creates pores in the membrane to accelerate the uptake of a co-delivered antigen by the antigen presenting cells. Multiple clinical trials using QS-21 as an adjuvant, demonstrated satisfactory safety profiles and enhanced immunogenicity in immunocompromised volunteers