A general method is described for the solid phase supported synthesis of DNA containing 3'-terminal phosphodiesters modified with linkers bearing either amino, thiol, or hydroxyl groups. These products are all made from a common intermediate, obtained by the reaction of trimellitic anhydride chloride with aminopropyl CPG. The anhydride-derivatized support was then reacted with three appropriate bifunctional spacers, giving DMT-protected hydroxyl solid supports bearing the masked functionality as an ester, amide, or thioester. DNA synthesis was then performed, followed by ammonia cleavage and deprotection, giving the hydroxyl-, amino-, or thiol-functionalized DNA 3'-phosphate diesters, respectively. Test mononucleotides synthesized with each of the new supports were identical with control mononucleotides made with 5'-immobilized nucleosides and alkylhydroxyl, alkylamino, and alkylthio phosphoramidites. The new supports were then used to prepare several 3'-modified oligonucleotides, which were characterized by gel electrophoresis, HPLC, and MALDI mass spectroscopy. The amino- and thiol-functionalized DNAs were conjugated with chromophores, and purification of these products was facilitated by use of reversed phase cartridges.
Canada has its cultural roots In the religious and political power struggles of the first half of the nineteenth century. During that period the Imperialists of England sought to maintain economic and political control of Canada While an emerging class of industrialists and commercial entrepreneurs within Canada were attempting to establish independent and autonomous political authority. At the same time the powerful Anglican and Roman Catholic Churches struggled vigorously to maintain their authoritative positions in administration of the colony. While many of the clergy were deeply involved in politics, the politicians were fighting political issues on religious principles; religion and politics were seriously interwoven. At this period the general population in both Upper and Lower Canada were struggling to free themselves from colonial domination and attempting to establish an autonomous, democratic government. However, in this struggle they were defeated. Although Canada eventually won political independence, she remained a colony economically and culturally. In a peculiar and perplexing manner, the Roman Catholic Church played a dominant role in sustaining colonialism through utilizing the principles of separatism and feUdalism. The Church of England, which until mid century was a prominent institution in the colony, also supported the forces of ImPerialism. Although the common people of the two provinces differed historically and religiously, their objectives for an autonomous Canadian society were basically similar; consequently '1n analogous Struggle took place in each. Unification of the two national groups
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