Hydrolysis of cyclosporin A: identification of 1,11 seco-cyclosporin A and 4,5 seco-isocyclosporin A by FAB-MS/MS.
We have previously reported that treatment of CsA with aqueous HCI gives rise to the formation of a number of water-soluble compounds. Two of these were identified from their FAB-MS/MS spectra as open-chain nona- and decapeptides. We describe here the identification of two other main compounds deriving from the same treatment. Identification was rendered possible from the comparison of their FAB-MS/MS spectra with those of methyl and acetyl derivatives. The two compounds are water-soluble, open-chain undecapeptides corresponding to 1.11 seco-CsA and of 4.5 seco-isoCsA, respectively.
Magni
F
F
Scientific Institute H. San Raffaele, Milan, Italy.
Arnoldi
L
L
Del Puppo
M
M
Galli Kienle
M
M
D000107:Acetylation; D000595:Amino Acid Sequence; D016572:Cyclosporine / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D003524:Cyclosporins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D006801:Humans; D006851:Hydrochloric Acid; D006868:Hydrolysis; D066298:In Vitro Techniques; D008745:Methylation; D008969:Molecular Sequence Data; D015394:Molecular Structure; D012995:Solubility; D016339:Spectrometry, Mass, Fast Atom Bombardment; D014867:Water
D003524:Cyclosporins; D014867:Water; C070226:isocyclosporin A; D016572:Cyclosporine; D006851:Hydrochloric Acid