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The thesis studied of anticoccidial drugs febrifugine and its analogues halofuginone synthesis . Bromoaniline , as raw materials, and the two-step reaction After Sandmyer and condensation to give 6 - bromoisatin , and then methanesulfonyl chloride chloride to give 5 - chloro-6 - bromoisatin . The latter under basic conditions to give 2 - amino - 4 - chloro - 5 - bromo- benzoic acid and 3% hydrogen peroxide reaction is further obtained with formamide condensation the halofuginone A fragment of 6 - chloro -7 - bromo -4 ( 3H ) - quinazoline ketone, total yield of 11.2% . Further, the inter- chlorotoluene as raw material , obtained by bromination , oxidation, and amination of 2 - amino -4 - chloro-5 - bromo- benzoic acid , and further with formamide condensation the halofuginone A fragment of 6 - chloro -7 - bromo-4 ( 3H ) - quinazolinone morpholinone , the total yield of 25.5% . This method is a short route , high yield , low cost with industrialization prospects . Meanwhile, the use of o- aminobenzoic acid has been condensed with formamide febrifugine A fragment 4 ( 3H ) - quinazolinone morpholinone , 73.0% yield of 3 - hydroxypyridine as raw material , after the amine protecting allylated , restoring, protecting group replacement , Claisen rearrangement of N-Cbz-2- allyl-3 - piperidone , and then by reduction, bromide febrifugine fragment B N-Cbz-2'- bromomethyl - piperidin- [3,2-b] furan intermediate , 22.5% of the total yield . The route readily available raw materials , reactions easy to operate , easy to industrialization . We tried a condensation reaction of the fragment A and fragment B intends to obtain halofuginone febrifugine , but has yet to obtain the target product , the reaction is still a further study .
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