- Synthesis and cytotoxic activity of conjugates of muramyl and normuramyl dipeptides with batracylin derivatives
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The synthesis of MDP (muramyl dipeptide) or nor-MDP (normuramyl dipeptide) conjugates modified at the peptide part with batracylin (BAT) or batracylin derivatives is described. Batracylin was synthesized by our modified method (Scheme 3). The synthesis of BAT via this modified route now appears to be feasible on a multigram scale. Preliminary screening data obtained at the National Cancer Institute (NCI, Bethesda, MD) have revealed that the conjugates did not expose any cytotoxic activity even at 10-4-10-8 M or μg/mL. During tests performed at Medical University of Gdansk, Poland, two analogues 11c and 11e reduced the proliferation of Ab melanoma cells in vitro compared with batracylin alone (Table 2, Figure 1).
- Dzierzbicka, Krystyna,Trzonkowski, Piotr,Sewerynek, Przemys?aw,My?liwski, Andrzej
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p. 978 - 986
(2007/10/03)
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- A Comparison of the Reactions of Some Ethyl N-Arylcarbamates with Those of the Corresponding Acetanilides. I. Nitration
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The reactions of some ethyl N-arylcarbamates and of the corresponding acetanilides towards 1 equiv. of sodium nitrate in concentrated sulfuric acid at 0-5 deg have been compared with one another and have been found to exhibit significant differences.Except in the case of the unsubstituted analogues, nitration of the carbamates was found to occur significantly more quickly than that of the acetanilides as shown by (i) a representative competitive nitration, and (ii) the fact the carbamates containing a nitro group are nitrated smoothly whereas the corresponding nitroacetanilides are slow to react.On the basis of competitive reactions, it is suggested that this difference in reactivity is due to steric factors.
- Rosevear, Judi,Wilshire, John F. K.
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p. 723 - 733
(2007/10/02)
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