Aspidosperma-type Alkaloids from Melodinus suaveolens

Cholinergic agonists or cholinomimetics mimic the action of acetylcholine to stimulate the parasympathetic nervous system. They are categorized into direct-acting and indirect-acting agents. The direct-acting cholinergic drugs induce the parasympathetic response by directly binding to the muscarinic or nicotine receptors. In comparison, the indirect-acting cholinergic drugs prevent acetylcholine hydrolysis, indirectly contributing to the extended parasympathetic response.
The direct-acting...

Cholinergic antagonists bind to cholinergic receptors and limit the effects of acetylcholine and other cholinergic agonists. Based on the specific cholinergic receptor affinity, these antagonists are classified as muscarinic or nicotinic. Anticholinergics interrupt parasympathetic innervations while sympathetic innervations remain uninterrupted. Muscarinic antagonists are also called 'muscarinic antagonists', 'antimuscarinics', or 'parasympatholytics'. Nicotinic...

Amines with low molecular weight are usually gaseous at room temperature, while those with high molecular weight are liquid or solids in nature. Usually, low molecular weight amines have a rotten fish-like smell. Diamines typically have a pungent smell. For instance, cadaverine and putrescine, depicted in Figure 1, are two molecules responsible for decaying tissue.

Microtubules are dynamic structures that undergo cycles of catastrophe and rescue. The microtubules play a central role in cell division by forming the spindle apparatus for segregating the chromosomes. This makes them ideal targets for regulating dividing cells in tumors and malignant cancer cells. Microtubule stabilizing drugs help stabilize the microtubule formation and promote its polymerization. Paclitaxel was the first microtubule stabilizing agent used as anticancer drug in chemotherapy...

Spasmolytic agents are drugs used to alleviate muscle spasms and spasticity. They can be categorized into different chemical groups based on their mechanisms of action. Centrally acting spasmolytics primarily affect the spinal cord, while others directly target skeletal muscle cells.
A major class of centrally acting spasmolytics is the α2-agonist, such as tizanidine. These drugs bind to α2-adrenoceptors, inhibiting the release of the excitatory neurotransmitter glutamate. They also...

Microtubules are dynamic structures and can be regulated by microtubule targeting agents (MTAs). Microtubule destabilizing drugs are a class of MTAs that destabilize and prevent microtubules' polymerization. Both natural and synthetic chemicals can be found under this class of drugs. Vincristine and vinblastine, two vinca alkaloids, and colchicine were among the first to be discovered. These drugs can affect cells in various ways, either by inducing a change in cell morphology, preventing...