| Autor: |
Nores GA; Department of Biochemical Oncology, Fred Hutchinson Cancer Research Center, Seattle, WA 98119., Hanai N, Levery SB, Eaton HL, Salyan EK, Hakomori S |
| Jazyk: |
angličtina |
| Zdroj: |
Carbohydrate research [Carbohydr Res] 1988 Aug 15; Vol. 179, pp. 393-410. |
| DOI: |
10.1016/0008-6215(88)84135-1 |
| Abstrakt: |
Various GM3 derivatives which are present in A431 cells have different effects on the activity of the EGF receptor kinase. In order to systematically study these effects, the following GM3 derivatives have been synthesized: de-N-acetyl-GM3 (D1), de-N-acetyl-lyso-GM3 (D2), lyso-GM3 (D3), de-N-acetyl-GM3 with N-acetylsphingosine (D4), and GM3 with N-acetylsphingosine (D3). A crucial step for the preparation of D1 is the use of mild alkaline conditions of hydrolysis under which the N-acetyl group of sialic acid is preferentially hydrolyzed. For the preparation of D3, conditions which allowed preferential N-acetylation of the amino group of the neuraminic acid moiety were devised, i.e., D2 was incorporated in a dipalmitoyl-phosphatidylcholine (dpPC) liposome in which the sphingosine moiety was protected and the amino group of neuraminic acid was N-acetylated with acetate and a water-soluble catalyst, 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide (DEC). When an aqueous micellar solution of D2 was treated with acetic anhydride and sodium hydrogencarbonate, N-acetylation occurred at the amino groups of both neuraminosyl and sphingosyl residues, yielding D5. The structures of these derivatives were verified by 1H-n.m.r. spectroscopy and mass spectrometry. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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