반응 #55421

반응 방정식

7-amino-3-[1-(2-carbamoylethyl)tetrazol-5-ylthiomethyl]-3-cephem-4-carboxylic acid

O-t-butyldiisopropylpseudourea

→

7-amino-3-[1-(2-carbamoylethyl)tetrazol-5-ylthiomethyl]-3-cephem-4-carboxylic acid t-butyl ester

용매

methylene chloride

methylene chloride

반응 조건

후처리

1. 1
   workup.ADDITIONTo a suspension of 19.3 g
2. 2
   기타The precipitate is removed by filtration
3. 3
   기타the filtrate is evaporated
4. 4
   기타to give a residue which
5. 5
   여과of benzene and filtered again
6. 6
   추출The filtrate is extracted with three 100 ml
7. 7
   workup.ADDITIONthe pH is adjusted to 7.5 by addition of solid sodium bicarbonate
8. 8
   기타The organic layer is separated
9. 9
   추출the aqueous phase is extracted with two 150 ml
10. 10
    건조The combined extracts are dried (MgSO4)
11. 11
    여과filtered
12. 12
    기타evaporated to dryness

실험 절차

To a suspension of 19.3 g. (0.05 mol.) of 7-amino-3-[1-(2-carbamoylethyl)tetrazol-5-ylthiomethyl]-3-cephem-4-carboxylic acid in 500 ml. of dry methylene chloride is added in one portion 30.0 g. (0.15 mol.) of O-t-butyldiisopropylpseudourea in 50 ml. of methylene chloride and the mixture is stirred at ambient temperature for 24 hours. The precipitate is removed by filtration and the filtrate is evaporated to give a residue which is taken up in 200 ml. of benzene and filtered again. The filtrate is extracted with three 100 ml. portions of cold 1N hydrochloric acid. The aqueous extracts are layered with ethyl acetate and the pH is adjusted to 7.5 by addition of solid sodium bicarbonate. The organic layer is separated and the aqueous phase is extracted with two 150 ml. portions of ethyl acetate. The combined extracts are dried (MgSO4), filtered and evaporated to dryness to give 7-amino-3-[1-(2-carbamoylethyl)tetrazol-5-ylthiomethyl]-3-cephem-4-carboxylic acid t-butyl ester.

출처