Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar structure may also be termed alkaloids. In addition to carbon, hydrogen and nitrogen, alkaloids may also contain oxygen or sulfur. More rarely still, they may contain elements such as phosphorus, chlorine, and bromine.
Aconitine is an alkaloid toxin produced by various plant species belonging to the genus Aconitum, known also commonly by the names wolfsbane and monkshood. Monkshood is notorious for its toxic properties.
Prostaglandins (PG) are a group of physiologically active lipid compounds called eicosanoids having diverse hormone-like effects in animals. Prostaglandins have been found in almost every tissue in humans and other animals. They are derived enzymatically from the fatty acid arachidonic acid. Every prostaglandin contains 20 carbon atoms, including a 5-carbon ring. They are a subclass of eicosanoids and of the prostanoid class of fatty acid derivatives.
Platelets or thrombocytes are a component of blood whose function is to react to bleeding from blood vessel injury by clumping, thereby initiating a blood clot. Platelets have no cell nucleus; they are fragments of cytoplasm derived from the megakaryocytes of the bone marrow or lung, which then enter the circulation. Platelets are found only in mammals, whereas in other vertebrates, thrombocytes circulate as intact mononuclear cells.
Tubulin in molecular biology can refer either to the tubulin protein superfamily of globular proteins, or one of the member proteins of that superfamily. α- and β-tubulins polymerize into microtubules, a major component of the eukaryotic cytoskeleton. Microtubules function in many essential cellular processes, including mitosis. Tubulin-binding drugs kill cancerous cells by inhibiting microtubule dynamics, which are required for DNA segregation and therefore cell division.
Prostacyclin (also called prostaglandin I2 or PGI2) is a prostaglandin member of the eicosanoid family of lipid molecules. It inhibits platelet activation and is also an effective vasodilator.
Thromboxane is a member of the family of lipids known as eicosanoids. The two major thromboxanes are thromboxane A2 and thromboxane B2. The distinguishing feature of thromboxanes is a 6-membered ether-containing ring.
P-selectin is a type-1 transmembrane protein that in humans is encoded by the SELP gene.
Thromboxane A synthase 1 , also known as TBXAS1, is a cytochrome P450 enzyme that, in humans, is encoded by the TBXAS1 gene.
Platelet factor 4 (PF4) is a small cytokine belonging to the CXC chemokine family that is also known as chemokine ligand 4 (CXCL4). This chemokine is released from alpha-granules of activated platelets during platelet aggregation, and promotes blood coagulation by moderating the effects of heparin-like molecules. Due to these roles, it is predicted to play a role in wound repair and inflammation. It is usually found in a complex with proteoglycan.
The thromboxane receptor (TP) also known as the prostanoid TP receptor is a protein that in humans is encoded by the TBXA2R gene, The thromboxane receptor is one among the five classes of prostanoid receptors and was the first eicosanoid receptor cloned. The TP receptor derives its name from its preferred endogenous ligand thromboxane A2.
Triflusal is a platelet aggregation inhibitor that was discovered and developed in the Uriach Laboratories, and commercialised in Spain since 1981. Currently, it is available in 25 countries in Europe, Asia, Africa and America. It is a derivative of acetylsalicylic acid (ASA)(Aspirin) in which a hydrogen atom on the benzene ring has been replaced by a trifluoromethyl group. Trade names include Disgren, Grendis, Aflen and Triflux.
Ibudilast is an anti-inflammatory drug used mainly in Japan, which acts as a phosphodiesterase inhibitor, inhibiting the PDE4 subtype to the greatest extent, but also showing significant inhibition of other PDE subtypes.
Aspirin causes several different effects in the body, mainly the reduction of inflammation, analgesia, the prevention of clotting, and the reduction of fever. Much of this is believed to be due to decreased production of prostaglandins and TXA2. Aspirin's ability to suppress the production of prostaglandins and thromboxanes is due to its irreversible inactivation of the cyclooxygenase (COX) enzyme. Cyclooxygenase is required for prostaglandin and thromboxane synthesis. Aspirin acts as an acetylating agent where an acetyl group is covalently attached to a serine residue in the active site of the COX enzyme. This makes aspirin different from other NSAIDs, which are reversible inhibitors. However, other effects of aspirin, such as uncoupling oxidative phosphorylation in mitochondria, and the modulation of signaling through NF-κB, are also being investigated. Some of its effects are like those of salicylic acid, which is not an acetylating agent.
Valentín Fuster Carulla, 1st Marquess of Fuster is a Spanish cardiologist and aristocrat.
Protopine is an alkaloid occurring in opium poppy, Corydalis tubers and other plants of the family papaveraceae, like Fumaria officinalis. Protopine is metabolically derived from the benzylisoquinoline alkaloid (S)-Reticuline through a progressive series of five enzymatic transformations: 1) berberine bridge enzyme to (S)-Scoulerine; 2) (S)-cheilanthifoline synthase/CYP719A25 to (S)-Cheilanthifoline; 3) (S)-stylopine synthase/CYP719A20 to (S)-Stylopine; 4) (S)-tetrahydroprotoberberine N-methyltransferase to (S)-cis-N-Methylstylopine; and ultimately, 5) N-methylstylopine hydroxylase to protopine.
Psychotridine is an alkaloid found in some species of the genus Psychotria, namely Psychotria colorata, but also Psychotria forsteriana, Psychotria lyciiflora, Psychotria oleoides, and Psychotria beccarioides. Psychotridine has analgesic effects and dose-dependently inhibits dizocilpine binding to cortical membranes in vitro, suggesting that it acts as a non-competitive NMDA receptor antagonist.
Israpafant (Y-24180) is a drug which acts as a selective antagonist for the platelet-activating factor receptor, and was originally developed for the treatment of asthma. Its chemical structure is a thienotriazolodiazepine, closely related to the sedative benzodiazepine derivative etizolam. However israpafant binds far more tightly to the platelet-activating factor receptor, with an IC50 of 0.84nM for inhibiting PAF-induced human platelet aggregation (compared to etizolam's IC50 of 998nM at this target), while it binds only weakly to benzodiazepine receptors, with a Ki of 3680nM. Israpafant has been found to inhibit the activation of eosinophil cells, and consequently delays the development of immune responses. It has also been shown to have anti-nephrotoxic properties, and to mobilize calcium transport.
Prolame, also known as 17β-( amino)estradiol, is a synthetic, steroidal estrogen and a 17β-aminoestrogen with anticoagulant effects that was first described in 1985 but was never marketed.
Bis(cyclopentadienyl)titanium(III) chloride, also known as the Nugent–RajanBabu reagent, is the organotitanium compound which exists as a dimer with the formula [(C5H5)2TiCl]2. It is an air sensitive green solid. The complex finds specialized use in synthetic organic chemistry as a single electron reductant.
