The synthesis of a new reagent 1-azobenzene-3-(5-nitro-2-pyridyl)-triazene(ABNPDT) and its colour reaction with cadimum were reported. At pH=10.40, in the presence of Triton X-100, ABNPDT react with cadimum to form a ...The synthesis of a new reagent 1-azobenzene-3-(5-nitro-2-pyridyl)-triazene(ABNPDT) and its colour reaction with cadimum were reported. At pH=10.40, in the presence of Triton X-100, ABNPDT react with cadimum to form a red Complex. The maximum absorption of reagent and complex are at 430nm and 520NM respectively. The molar absorpitivity is 2.0710 5L·mol -1 ·cm -1 . Berr’s law can be applied in the rang of 0～12μg/25ml. This method was used to determine tarce cadmium in water with satisfactory results.展开更多
Hydroxy-16α,17α,21-trimethyl-5-en-20-one was synthesized from 3α-acetoxypregna-5,16-dien-20-one and characterized by elemental analysis, 1H NMR, MS and IR. 16α,17α-Dimethyl steroid was formed by treatment of 3β-...Hydroxy-16α,17α,21-trimethyl-5-en-20-one was synthesized from 3α-acetoxypregna-5,16-dien-20-one and characterized by elemental analysis, 1H NMR, MS and IR. 16α,17α-Dimethyl steroid was formed by treatment of 3β-acetoxypregna-5,16-dien-20-one with methylmagnesium bromide, followed by reaction of the resulting 17(20)-enolate with methyl iodide. The main by- products were 3β-hydroxy-16α,17α-dimethyl-5-en-20-one. LHDMS([(CH 3) 3Si] 2NLi) and LDA([(CH 3) 2CH] 2NLi) were chosen as proper reagents for 21-position alkylation. The almost quantitative conversion of 16α,17α-dimethyl corticosteroid was achieved and the highest yield of the 16α,17α,21-trimethyl corticosteroid was 78%. The optimum reaction temperature was -20 ℃ for 16α,17α- dialkylation and was -50 ℃ for 21- position alkylation.展开更多
文摘The synthesis of a new reagent 1-azobenzene-3-(5-nitro-2-pyridyl)-triazene(ABNPDT) and its colour reaction with cadimum were reported. At pH=10.40, in the presence of Triton X-100, ABNPDT react with cadimum to form a red Complex. The maximum absorption of reagent and complex are at 430nm and 520NM respectively. The molar absorpitivity is 2.0710 5L·mol -1 ·cm -1 . Berr’s law can be applied in the rang of 0～12μg/25ml. This method was used to determine tarce cadmium in water with satisfactory results.
文摘Hydroxy-16α,17α,21-trimethyl-5-en-20-one was synthesized from 3α-acetoxypregna-5,16-dien-20-one and characterized by elemental analysis, 1H NMR, MS and IR. 16α,17α-Dimethyl steroid was formed by treatment of 3β-acetoxypregna-5,16-dien-20-one with methylmagnesium bromide, followed by reaction of the resulting 17(20)-enolate with methyl iodide. The main by- products were 3β-hydroxy-16α,17α-dimethyl-5-en-20-one. LHDMS([(CH 3) 3Si] 2NLi) and LDA([(CH 3) 2CH] 2NLi) were chosen as proper reagents for 21-position alkylation. The almost quantitative conversion of 16α,17α-dimethyl corticosteroid was achieved and the highest yield of the 16α,17α,21-trimethyl corticosteroid was 78%. The optimum reaction temperature was -20 ℃ for 16α,17α- dialkylation and was -50 ℃ for 21- position alkylation.
