N6-alkyladenosines and adenines labelled with tritium

New cytokinin metabolites in IPT transgenic Arabidopsis thaliana plants

“…1. The Z9GOG side chain ( N ‐[( E )‐4‐ t ‐butoxy‐3‐methylbut‐2‐enyl]phthalimide (1a) was prepared as described previously (Orosnik and Mallory 1950, Corse and Kuhnle 1972, Hanuš et al 2000). Acidolysis of the t ‐butyl group of 1a with trifluoroacetic acid was accompanied by O ‐trifluoroacetylation of 1b.…”

“…A solution containing 1a (Orosnik and Mallory 1950, Corse and Kuhnle 1972, Hanuš et al 2000) (1 g, 3.6 mmol) in 10 ml dry trifluoroacetic acid was left to stand at room temperature for 16 h. After evaporation of the acid under reduced pressure, the mixture of 1b and its O ‐trifluoracetyl derivative was dissolved in 15 ml of methanol and the solution triturated slowly with 0.2–0.5 equivalents of sodium methanolate in methanol. Hydrolysis of the trifluoroacetate was monitored using TLC (system A; 1b: R f 0.15, O ‐trifluoroacetate of 1b: R f 0.75).…”

Cytokinin N-glucosides: Occurrence, Metabolism and Biological Activities in Plants

“…All samples were analyzed by passing the HPLC eluate through a radioactivity flow detector (Ramona 2000; Raytest GmbH, Straubenhardt, Germany) coupled to the HPLC Ultimate 3000 chromatograph (for more details see Section 2.4 ). All [ 3 H]CKs used in the bioassay ([2- 3 H]iP, [2- 3 H] t Z, and [2- 3 H] t Z9G) were synthesized as previously reported for N 6 -alkyladenosines labeled with tritium [ 57 ].…”

Cytokinin N‐glucosylation inhibitors suppress deactivation of exogenous cytokinins in radish, but their effect on active endogenous cytokinins is counteracted by other regulatory mechanisms

“…Tritiated dihydrozeatin (DHZ) and isopentenyladenine (iP) were prepared according to Hanus̆ et al (2000) by catalytic dehalogenation of 2‐chloroadenosine with tritium gas and subsequent alkylation with either (E)‐4‐t‐butoxy‐3‐methylbut‐2‐enyl bromide or with 3‐methylbut‐2‐enyl bromide and acidic hydrolysis. [ 3 H]BA was prepared by alkylation of tritiated adenosine with benzyl bromide and subsequent hydrolysis.…”