Pyrrole Alkaloids

Kainic acid is a potent excitotoxic agent. Kainic acid hydrate also is an agonist for a subtype of ionotropic glutamate receptor. Kainic acid induces seizures.

Monocrotaline is an 11-membered macrocyclic pyrrolizidine alkaloid. Monocrotaline inhibits OCT-1 and OCT-2 with IC₅₀s of 36.8 µM and 1.8 mM, respectively. Monocrotaline has antitumor activity and is cytotoxic to hepatocellular carcinoma cells. Monocrotaline is used to induce a model of pulmonary hypertension in rodents. ^[2][6][8].

Homoharringtonine (Omacetaxine mepesuccinate;HHT) is a cytotoxic alkaloid with antitumor properties which acts by inhibiting translation elongation.

Harringtonine is a natural Cephalotaxus alkaloid that inhibits protein synthesis. Harringtonine has anti-chikungunya virus (CHIKV) activities with an EC₅₀ of 0.24 μM.

Cardiotoxin Analog (CTX) IV (6-12) TFA is a membrane active peptide that specifically targets negatively charged phospholipid membranes (such as phosphatidylserine and phosphatidylinositol). Cardiotoxin Analog (CTX) IV (6-12) TFA was discovered in the venom of the Taiwan cobra. Cardiotoxin Analog (CTX) IV (6-12) TFA is a chemically synthesized snake venom cardiotoxin that binds to cell membranes and embeds into lipid bilayers through hydrophobic interactions and electrostatic attraction, thereby destroying the stability of membrane structure. Cardiotoxin Analog (CTX) IV (6-12) TFA can induce membrane lipid disorder and cell lysis, exhibiting hemolysis and cytotoxicity.

Isoconessimine is a steroidal alkaloid that can be found in the seeds of Holarrhena antidysenterica, and the IC₅₀ value of its acetylcholinesterase inhibitory activity is > 300 μM.

Petasinine is an alkaloid. Petasinine can be isolated from Petasites japonicus Maxim.

3-(2'-Aminophenyl)-pyrrole is a pyrrole derivative. 3-(2'-Aminophenyl)-pyrrole is derived from Filobacter thaii, a novel marine gliding bacterium.

Lycorine is a natural alkaloid extracted from the Amaryllidaceae plant. Lycorine is a potent and orally active SCAP inhibitor with a K_d value 15.24 nM. Lycorine downregulates the SCAP protein level without changing its transcription. Lycorine is also a melanoma vasculogenic inhibitor. Lycorine can be used for the study of prostate cancer and metabolic diseases.

Cyclopiazonic acid is an endoplasmic reticulum calcium ATPase (ECAs) inhibitor and human respiratory syncytial virus (RSV) inhibitor (EC₅₀ value of 4.13 μ M), which can reduce the antagonistic effect of 5-HT receptors in rat thoracic aorta, induce p53 dependent cell apoptosis and reproductive toxicity in mouse testes, and inhibit the biological activation of aflatoxin B^[1][4][5].

Swainsonine (Tridolgosir) is an natural indolizidine alkaloid, a potent and reversible α-mannosidase inhibitor. Swainsonine induces apoptosis and cell cycle arrest at G2/M phase. Swainsonine shows anti-tumor activity.

Ferroheme is the ferrous form of heme in hemoglobin, reversibly binding oxygen as an oxygen carrier. Its free form induces oxidative stress and ferroptosis by releasing iron ions, which catalyze reactive oxygen species generation via Fenton reactions, leading to lipid peroxidation and cell death. This mechanism is critical in pathological contexts like intracerebral hemorrhage and neurodegenerative diseases, making it a target for studying iron-overload disorders and ferroptosis-related pathologies[1][2][3].

L-Hydroxyproline, one of the hydroxyproline (Hyp) isomers, is a useful chiral building block in the production of many pharmaceuticals.

BPC 157 is the 15-amino acide fragment of gastric peptide BPC. BPC 157 exhibits wound healing promoting and neuroprotective activity. BPC 157 maintains the integrity of the gastrointestinal mucosa without significant toxicity. BPC 157 acetate counteracts NSAIDs/insulin overdose/copper-induced toxicity. BPC 157 ameliorates specific (over)stimulated/damaged neurotransmitter systems-induced behavioral disorders through serotonergic and dopaminergic systems.

Lycorine hydrochloride is the main active ingredient of the herbal medicine derived from Lycoris radiata (L’Her.) Herb. and is also a melanoma vasculogenic inhibitor and has anti-tumor activity. Lycorine hydrochloride effectively inhibits mitotic proliferation of Hey1B cells (IC₅₀ of 1.2 μM).

Biliverdin hydrochloride, a tetrapyrrolic pigment, is a product of heme catabolism. Heme is broken down into Biliverdin and carbon monoxide and iron by heme oxidase. Biliverdin hydrochloride is then quickly broken down to bilirubin by Biliverdin reductase. Biliverdin hydrochloride is anti-mutagenic, an antioxidant, anti-inflammatory, and immunosuppressant.

Queuine is a selective substrate for tRNA guanine transglycosylase (TGT) and can be incorporated into eukaryotic tRNA. Queuine promotes tRNA modification, affecting mitochondrial function and Warburg metabolic phenotype. If Queuine is deficient, aerobic glycolysis can be enhanced, oxidative phosphorylation can be inhibited, and Warburg metabolism can be promoted, accompanied by increased ammonia and lactate production and increased lactate dehydrogenase activity. Queuine can be used for autoimmune diseases (such as experimental models of multiple sclerosis) and cancer metabolic regulation, and its deficiency is associated with low tRNA modification in tumor cells.

Stachydrine is a major constituent of Chinese herb leonurus heterophyllus sweet used to promote blood circulation and dispel blood stasis. Stachydrine can inhibit the NF-κB signal pathway.

Maleimide can be used for production of antibody-drug conjugate (ADC) which is used in cancer research. Maleimide also be leveraged for the preparation of fluorogenic probe, which is mainly used for the specific detection of thiol analytes.

Cotinine ((-)-Cotinine) is an orally active alkaloid found in tobacco and is the primary metabolite of nicotine. Cotinine is metabolized by CYP2A13 into trans-3'-hydroxycotinine. Cotinine is used as a biomarker to measure exposure to tobacco smoke components. Cotinine has vasodepressor activity. The mixture of cotinine and nicotine (Nicotine) has antiproliferative activity against pterygium. (S)-(-)-Cotinine activates nicotinic acetylcholine receptors (nAChR) in a calcium-dependent manner, leading to the release of dopamine (Dopamine, HY-B0451). Cotinine ((-)-Cotinine) is used in research related to cardiovascular and inflammatory diseases.