P. I. Zakharov

Mass-spectrometric study of the coumarins mogoltin, mogoltavin, and mogoltavinin

ConclusionsThe mass spectra of six compounds belonging to the class of terpenoid coumarins and of four of their deuterium analogs have been studied. Decomposition pathways for these substances under the action of electron impact have been suggested. It has been shown that from the mass spectra of compounds of this series it is possible to determine their molecular weights and, in atomic mass units, the weights of their terpene moieties, and also to establish the presence of hydroxy and acyloxy groups in the bicyclic terpene moiety.

Mass-spectrometric distinction of linear and angular 2,2'-dimethyl-3'-oxo-dihydropyranocoumarins

SummaryThe mass spectra of linear and angular 2′,2′-dimethyl-3′-oxodihydropyranocoumarins and their deuterium analogs have been studied. A basic mass-spectrometric difference between these substances has been found which consists in the greater stability of the fragment (M - CO)+. for the linear isomer than for the angular isomer. A hypothesis has been put forward on the most probable route for the formation of the ion (M - 2CO - H)+ in the mass spectra of the compounds mentioned.

Mass-spectrometric distinction of linear and angular 3′,4′-dihydroxy-substituted dihydropyranocoumarins and their derivatives

SummaryThe dissociative ionization of four linear dihydropyranocoumarins and three of their deuterium analogs has been studied. It has been shown that by means of the mass-spectrometric method it is possible to determine the type of linkage of the dihydropyrane ring with the coumarin ring for each pair of linear and angular isomers in this series of substances, to determine the presence of hydroxy or methoxy groups in position 4′ of their molecules, and to distinguish the presence of the acyl residue of senecioic acid from that of angelic acid in the products of the partial hydrolysis and methanolysis of 3′,4′-diacyloxydihydropyranocoumarins.

Low-voltage mass spectra of monohydroxy-and monoacyloxydihydropyranocoumarins and -dihydrofurocoumarins

SummaryWith the aid of the low-voltage mass spectra of 16 compounds belonging to the monohydroxy- and monoacyloxydihydropyranocoumarins and -dihydrofurocoumarins and their deuterium analogs it has been shown the relative intensities of the ions with m/e 176 and 175 is an analytical magnitude both for the dihydropyranocoumarins and the dihydrofurocoumarins which enables linear and angular isomers in these series of substances to be distinguished.

Chemical ionization mass spectra of natural monohydroxy- and monoacyloxy-substituted dihydropyranocoumarins and dihydrofurocoumarins

SummaryThe chemical ionization mass spectra of ten compounds of the group of natural monohydroxy and monoacyloxy derivatives of dihydropyranocoumarins and dihydrofurocoumarins have been studied. Their difference from the electron impact mass spectra has been shown. The structural-analytical possibilities of the method of chemical ionization for this series of substances has been determined.

A mass-spectrometric study of the dihydrocoumarin sachalinin

SummaryThe presence of a 2″-hydroxypropenyl grouping at C5′ of sachalinin appreciably changes its fragmentation as compared with columbianetin, which contains a hydroxypropyl radical in the same position.

Mass-spectrometric study of some derivatives of furo- and dihydrofurocoumarins

SummaryThe mass spectra of eight compounds beloning to the class of linear furo- and dihydrofurocoumarins have been studied. A scheme of the fragmentation of these substances under the action of electron impact has been proposed. It has been shown that the mass-spectrometric method permits acyl derivatives of oreoselone to be distinguished reliably from acyl derivatives of dihydrooreoselol and the latter series of substances from derivatives isomeric with them belonging to the class of dihydrofuro- and dihydropyranocoumarins.

A mass-spectrometric study of linear monohydroxy-and monoacyloxydihydrofurocoumarins

SummaryThe mass spectra of the following six linear monohydroxy- and monoacyloxydihydrofurocoumarins have been studied: marmezin (I), [D]marmezin (II), O-acetylmarmezin (III), deltoin (IV), pranchimgin (V), and seseliflorin (VI). It has been shown that it is possible by the mass-spectrometric method of analysis to determine the molecular weights of the acids the acyl radicals of which are present in these substances, to distinguish the acyl radical of angelic acid from that of senecionic acid, and also to distinguish this class of compounds from the angular dihydrofurocoumarins and from the angular and linear dihydropyranocoumarins isomeric with them.

A mass-spectrometric study of angular and linear diacyloxydihydrofurocoumarins

SummaryThe mass spectra of six compounds belonging to the class of angular and linear 4′-acyloxy-5′-(1-acyloxy-1-methylethyl)-and 4′-methoxy-5′-(1-acyloxy-1-methylethyl)dihydrofurocoumarins have been obtained. It has been shown that from the mass spectra of this class of compounds it is possible to determine the molecular weights of the acids correspnding to the acyl radicals that they contain, the position of attachment of the dihydrofuran ring to the coumarin ring, and the positions of the acyl residues, and also to distinguish this class of substances from the class of diacyloxydihydropyranocoumarins isomeric with it.

A mass spectrometric study of some dihydropyranocoumarins

SummaryThe mass spectra of ten angular and linear dihydropyranocoumarins without substituents and with hydroxy and acyloxy substituents in position 3 of the dimethylchroman ring have been studied. Depending on the presence and nature of these substituents the mass spectra of the compounds considered have different relative intensities of the fragments with m/e 228, 213, 176, 175, 83, and 85, which permits mass spectrometry to be used in this group of compounds for structural-analytical purposes.