Discovery and development of direct Xa inhibitors Xa was identified as a promising target for the development of new anticoagulants in the early 1980s. In 1987 the first factor Xa inhibitor, the naturally occurring compound antistasin, was isolated from the salivary glands of the Mexican leech "Haementeria officinalis". Antistasin is a polypeptide and a potent Xa inhibitor. In 1990 another naturally occurring Xa inhibitor was isolated, tick anticoagulant peptide (TAP) from extracts of the tick "Ornithodoros moubata". TAP and antistasin were used to estimate factor Xa as a drug target. Blood coagulation is a complex process by which the blood forms clots. It is an essential part
Naturally occurring phenols use 2-methoxy-4-vinylphenol for chemical signaling (pheromones). Other simple and complex phenols can be found in eusocial ants (such as Crematogaster) as components of venom. In female elephants, the two compounds 3-ethyl phenol and 2-ethyl 4,5 dimethylphenol have been detected in urine samples. Temporal glands secretion examination showed the presence of phenol, m-cresol and p-cresol (4-methyl phenol) during musth in male elephants. p-Cresol and o-cresol are also components of the human sweat. P-cresol is also a major component in pig odor. 4-Ethylphenol, 1,2-dihydroxybenzene, 3-hydroxyacetophenone, 4-methyl-1,2-dihydroxybenzene, 4-methoxyacetophenone, 5-methoxysalicylic acid, salicylaldehyde, and 3-hydroxybenzoic acid are components of castoreum, the exudate from the castor