Reactions it shows the properties of a hydroxylic substance.
It crystallizes from benzene in prisms, which melt at 97° C. Sodium nitrite in the presence of excess of acid converts it into the corresponding hydroxylic compound flavenol.
The subject has been especially studied by Skraup, Konigs, and von Miller; Kiinigs and von Miller have proposed formulae consisting of a piperidine ring substituted with a vinyl group; in the former that is a bridge of CH 2 C(OH) from the nitrogen atom to the -y-carbon atom, connexion with the quinoline residue being made at the hydroxylic carbon atom through a CH2 group: whilst in the latter the piperidine ring is substituted by a methyl group in addition to the vinyl group and the bridge is simply C(OH), with which connexion is made as before.
The /3 compound is hydroxylic in character, whilst the a and -y derivatives behave frequently as if they possess the tautomeric ketostructure, yielding according to the conditions of the experiment either N- or 0-ethers (H.
ESTERS, in organic chemistry, compounds formed by the condensation of an alcohol and an acid, with elimination of water; they may also be considered as derivatives of alcohols, in which the hydroxylic hydrogen has been replaced by an acid radical, or as acids in which the hydrogen of the carboxyl group has been replaced by an alkyl or aryl group. In the case of the polybasic acids, all the hydrogen atoms can be replaced in this way, and the compounds formed are known as "neutral esters."