title: Mass spectrometry and chromatography of t-butyldimethylsilyl derivatives of cytokinin bases.
abstract: Di-(t-butyldimethylsilyl) derivatives of the cytokinin bases zeatin, cis-zeatin, and dihydrozeatin may be prepared quantitatively in the presence of dimethylaminopyridine. These derivatives have good gas chromatographic properties and are very suitable for gas chromatography-mass spectrometry analysis of cytokinin bases. The t-butyldimethylsilyl (tBuDMS) group at N-9 may be selectively hydrolyzed and the resulting mono-O-silyl derivatives are sufficiently stable to be subjected to thin-layer chromatography and high-performance liquid chromatography. The mass spectral fragmentation of the mono- and di-tBuDMS derivatives of adenine, zeatin, cis-zeatin, and dihydrozeatin and also of the mono-tBuDMS derivatives of N6-isopentenyladenine and 6-benzylaminopurine have been rationalized. The 9-tBuDMS moiety was characterized by an elimination of isobutene (M-56) and of isobutene plus a methyl radical (M-56-15).
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D003583:Cytokinins / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D017646:Organosilicon Compounds; D010937:Plant Growth Regulators / Q000032:analysis*; D012825:Silicon / Q000032:analysis*; D015026:Zeatin / Q000032:analysis
chemical_list: D003583:Cytokinins; D017646:Organosilicon Compounds; D010937:Plant Growth Regulators; C009660:t-butyldimethylsilyl compounds; D015026:Zeatin; D012825:Silicon