Summary. Background: Previous reports have noted that factor (F) XI and FXII and prekallikrein (the contact phase proteases) are absent in fish. Objectives: A broad survey of recently completed genomes was undertaken to find where during the course of vertebrate evolution these coagulation factors appeared. Methods: BLAST searches were conducted for the various factors on genomes of lamprey, puffer fish, zebra fish, frog, chicken, platypus, and opossum. Results: It was confirmed that FXII is absent from fish; it is present in frog, platypus, and opossum, but is absent in chicken, an apparent example of gene loss. A single gene corresponding to the evolutionary predecessor of FXI and prekallikrein occurs in frog, chicken, and platypus. The opossum (a marsupial) has both prekallikrein and FXI, completing the full complement of these genes that occurs in eutherian mammals. Conclusions: The step‐by‐step accrual of genes for these factors by a series of timely gene duplications has been confirmed by phylogenetic analysis and other considerations.

Many natural coumarins and their chemically synthesized analogs and derivatives exert diverse properties, such as anticancer, antioxidant, anti-inflammatory, or anticoagulant, with the latter being of the utmost importance. The widely used warfarin, acenocoumarol, and phenprocoumon exert anticoagulant properties by inhibiting the vitamin K epoxide reductase complex. In this interdisciplinary review, we present biochemical principles of the coagulation processes and possible methods for their tuning based on the use of coumarins. We also summarize chemical methods of synthesis of coumarins and discuss structures and properties of those that have been used for a long time, as well as newly synthesized compounds. Brief information on the clinical use of coumarins and other anticoagulant drugs is given, including the severe effects of overdosing and methods for reversing their action.