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2025
It is built from checkable properties of the record itself: whether the article has a DOI, how many independent sources confirmed its data, whether the required fields are filled in, and how recent the latest confirmation is. Disagreement between sources and a missing identifier lower it. A value of 80 or above means the record was published without further checking; 60 to 79 means it is published at reduced confidence, with a manual check advisable. A record verified by an editor by hand is never pushed below 90 by a recalculation. This scores our data about the article, not the article itself.
New phosphacoumarins containing an aldehyde group at the periphery were obtained in a ‘one-pot’ reaction of 2-ethoxyvinylphosphonic dichloride with 2,4-dihydroxybenzaldehyde derivatives. The further reaction of these compounds with 2,4-dinitrophenylhydrazine afforded new hydrazones which exist only as E-isomers.