Indole Alkaloids

Staurosporine is a potent, ATP-competitive and non-selective inhibitor of protein kinases with IC₅₀s of 6 nM, 15 nM, 2 nM, and 3 nM for PKC, PKA, c-Fgr, and Phosphorylase kinase respectively. Staurosporine also inhibits TAOK2 with an IC₅₀ of 3 μM. Staurosporine is an apoptosis inducer.

Caerulein is a decapeptide and a potent cholecystokinin receptor agonist. Caerulein is a safe and effective cholecystokinetic agent with a direct spasmogenic effect on the gallbladder muscle and bile ducts.

Serotonin (5-Hydroxytryptamine) hydrochloride is a monoamine neurotransmitter in the CNS and an endogenous 5-HT receptor agonist, with blood-brain barrier permeability. Serotonin hydrochloride is also a catechol O-methyltransferase (COMT) inhibitor with a K_i of 44 μM.

Serotonin is a monoamine neurotransmitter in the CNS and an endogenous 5-HT receptor agonist. Serotonin is also a catechol O-methyltransferase (COMT) inhibitor with a K_i of 44 μM.

Indole-3-pyruvic acid is an orally active ketone analog of tryptophan, and is an aryl hydrocarbon receptor (AHR) agonist. Indole-3-pyruvic acid inhibits p38/MAPK phosphorylation, regulates the tryptophan metabolic pathway, and also possesses protective activities against skin photodamage, as well as anti-inflammatory and anti-anxiety bioactivities in the gut. Indole-3-pyruvic acid can downregulate the expression of IL-1β, IL-6, Cox-2, and Bax to alleviate UVB-induced keratinocyte toxicity. Indole-3-pyruvic acid can activate AHR to promote Tr1 cell differentiation, increase IL-10, and inhibit Th1 cytokine production. Indole-3-pyruvic acid can alter the levels of kynurenine metabolites in the brain, mediating central nervous system-related effects. Indole-3-pyruvic acid can be used in research on skin lesions, colitis, and anxiety.

Indole-3-carboxylic acid is an orally active urinary indolic tryptophan metabolite. Indole-3-carboxylic acid is a mediator of priming against Plectosphaerella cucumerina. Indole-3-carboxylic acid enhances the anti-colorectal cancer potency of Doxorubicin (HY-15142A) by inducing cell senescence. Indole-3-carboxylic acid can be used in liver disease research.

Fumitremorgin C is a potent and selective ABCG2/BRCP inhibitor.

Oxindole (Indolin-2-one) is an aromatic heterocyclic building block. 2-indolinone derivatives have become lead compounds in the research of kinase inhibitors.

Harmine is a natural dual-specificity tyrosine phosphorylation-regulated kinase (DYRK) inhibitor with anticancer and anti-inflammatory activities. Harmine has a high affinity of 5-HT_2A serotonin receptor, with an K_i of 397 nM.

Yohimbine hydrochloride is an alpha-2 renal adenomatase receptor inhibitor, blocking pre- and post-contact alpha-2 renal adenomatase receptors, causing the release of renal adenoma and multiple sclerosis.

Reserpine is an inhibitor of the vesicular monoamine transporter 2 (VMAT2).

Indole-3-carboxaldehyde (3-Formylindole), a banlangen extract, is the product of the oxidative degradation of indole-3-acetic acid (IAA) by crude enzyme preparations from etiolated pea seedlings. Indole-3-carboxaldehyde is a biochemical used to prepare analogs of the indole phytoalexin cyclobrassinin. Indole-3-carboxaldehyde also enhances the epithelial barrier and anti-inflammatory activity in the intestinal tract.

Indole-3-carbinol (I3C) inhibits NF-κB activity and also is an Aryl hydrocarbon receptor (AhR) agonist, and an inhibitor of WWP1 (WW domain-containing ubiquitin E3 ligase 1).

Coumarin 6, a fluorescent dye, is used as a fluorescent probe in a microparticle drug delivery system to conduct in vivo tracking, cell uptake, and transport mechanism studies of drug delivery systems (λ_exc=450 nm, λ_em=505 nm).

Indole is an aromatic, heterocyclic, organic compound which widely distributed in the natural environment and can be produced by a variety of bacteria. Indole regulates various aspects of bacterial physiology, including spore formation, plasmid stability, resistance to drugs, biofilm formation, and virulence as an intercellular signal molecule.

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].

Evodiamine is an alkaloid isolated from the fruit of Evodia rutaecarpa Bentham with diverse biological activities including anti-inflammatory, anti-obesity, and antitumor.

Indirubin (Couroupitine B) is a bis-indole alkaloid and has emarkable anticancer activity against chronic myelocytic leukemia.

Tryptamine is a selective, blood-brain-penetrating 5-HT4 receptor agonist (EC50=1-3 mM) and an endogenous ligand of the aryl hydrocarbon receptor (AHR) (Kd=10-50 nM). Tryptamine promotes intestinal anion secretion and fluid transport by activating G protein-coupled receptors (GPCRs) and accelerates gastrointestinal motility. Tryptamine regulates Th17/Treg balance to inhibit neuroinflammation, competitively binds to 5-HT receptors to regulate central nervous system activity, and participates in temperature regulation and spinal reflex regulation as a neuromodulator. Tryptamine can be used to study intestinal motility disorders such as functional constipation, and has shown significant efficacy in multiple sclerosis models.

K-252a, a staurosporine analog, inhibits protein kinase, with IC₅₀ values of 470 nM, 140 nM, 270 nM, and 1.7 nM for PKC, PKA, Ca²⁺/calmodulin-dependent kinase type II, and phosphorylase kinase, respectively. K-252a is a potent inhibitor (IC₅₀ of 3 nM) of the tyrosine protein kinase (TRK) activity of the NGF receptor gp140trk, the product of the trk protooncogene.