Abstract: The present invention discloses novel and improved nucleosidic and nucleotidic compounds that are useful in the light-directed synthesis of oligonucleotides, as well as, methods and reagents for their preparation. These compounds are characterized by novel photolabile protective groups that are attached to either the 5?- or the 3?-hydroxyl group of a nucleoside moiety. The photolabile protective group is comprised of a 2-(2-nitrophenyl)-ethyoxycarbonyl skeleton with at least one substituent on the aromatic ring that is either an aryl, an aroyl, a heteroaryl or an alkoxycarbonyl group. The present invention includes the use of the aforementioned compounds in light-directed oligonucleotide synthesis, the respective assembly of nucleic acid microarrays and their application.

Abstract: The present invention discloses novel and improved nucleosidic and nucleotidic compounds that are useful in the light-directed synthesis of oligonucleotides, as well as, methods and reagents for their preparation. These compounds are characterized by novel photolabile protective groups that are attached to either the 5?- or the 3?-hydroxyl group of a nucleoside moiety. The photolabile protective group is comprised of a 2-(2-nitrophenyl)-ethyoxycarbonyl skeleton with at least one substituent on the aromatic ring that is either an aryl, an aroyl, a heteroaryl or an alkoxycarbonyl group. The present invention includes the use of the aforementioned compounds in light-directed oligonucleotide synthesis, the respective assembly of nucleic acid microarrays and their application.

Abstract: The present invention discloses novel and improved nucleosidic and nucleotidic compounds that are useful in the light-directed synthesis of oligonucleotides, as well as, methods and reagents for their preparation. These compounds are characterized by novel photolabile protective groups that are attached to either the 5?- or the 3?-hydroxyl group of a nucleoside moiety. The photolabile protective group is comprised of a 2-(2-nitrophenyl)-ethyoxycarbonyl skeleton with at least one substituent on the aromatic ring that is either an aryl, an aroyl, a heteroaryl or an alkoxycarbonyl group. The present invention includes the use of the aforementioned compounds in light-directed oligonucleotide synthesis, the respective assembly of nucleic acid microarrays and their application.

Abstract: The present invention discloses novel and improved nucleosidic and nucleotidic compounds that are useful in the light-directed synthesis of oligonucleotides, as well as, methods and reagents for their preparation. These compounds are characterized by novel photolabile protective groups that are attached to either the 5′- or the 3′-hydroxyl group of a nucleoside moiety. The photolabile protective group is comprised of a 2-(2-nitrophenyl)-ethyoxycarbonyl skeleton with at least one substituent on the aromatic ring that is either an aryl, an aroyl, a heteroaryl or an alkoxycarbonyl group. The present invention includes the use of the aforementioned compounds in light-directed oligonucleotide synthesis, the respective assembly of nucleic acid microarrays and their application.

Abstract: The invention relates to nucleoside derivatives with photolabile protecting groups of general formula (I) wherein R1 is H, F, Cl, Br, I, or NO2; R2 is H or CN, provided that R1 and R2 are not simultaneously H; R3 is H, 1-4 C alkyl, or phenyl; R4 is H or a conventional functional group for the synthesis of oligonuleotides; R5 is H, OH, halogen or XR6, where X=O or S, and R6 is a conventional nucleotide protecting group; and B is adenine, cytosine, guanine, thymine, uracil, 2,6-diaminopurin-9-yl, hypoxanthin-9-yl, 5-methylcytosin-1-yl, 5-amino-4-imidazolcarboxamid-1-yl or 5-amino-4-imidazolcarboxamid-3-yl, where, if B is adenine, cytosine or guanine the primary amine functionality, optionally, carries a permanent protecting group. Furthermore, these derivatives may be used for the light-controlled synthesis of oligonucleotides on a DNA chip.

Abstract: The invention relates to a method for the specific photolytic deprotection of nucleoside derivatives that are immobilized on a substrate, especially for use in the production of DNA chips. Said method is characterized in that a gel or viscous liquid layer is applied on the nucleoside derivatives that are immobilized on a substrate. Said gel or viscous liquid contains one or more polymer compounds and at least one representative from the group comprising water, water/C1-C4 alcohol mixtures and polar aprotic solvents. For initiating the deprotection, the nucleoside derivates are irradiated. This method favors a rapid, clean and complete removal of the photolabile protective groups from the nucleoside derivatives, which results in the required purity of the synthesized nucleotide or oligonucleotide sequences.

Abstract: The invention relates to a method for producing 1-methyl-3-nitroguanidine. According to said method, nitroguanidine is reacted with methylamine and/or a methylammonium salt in an aqueous solution, at temperatures of 30 to 60° C. and at a pH value of 95 to 12.3. In this way, yields of 1-methyl-3-nitroguanidine of at least 80% and degrees of purity>99% can be obtained in a particularly environmentally friendly and technically simple way.

Abstract: The invention relates to a method for the specific photolytic deprotection of nucleoside derivatives that are immobilized on a substrate, especially for use in the production of DNA chips. Said method is characterized in that a gel or viscous liquid layer is applied on the nucleoside derivatives that are immobilized on a substrate. Said gel or viscous liquid contains one or more polymer compounds and at least one representative from the group comprising water, water/C1-C4 alcohol mixtures and polar aprotic solvents. For initiating the deprotection, the nucleoside derivates are irradiated. This method favors a rapid, clean and complete removal of the photolabile protective groups from the nucleoside derivatives, which results in the required purity of the synthesized nucleotide or oligonucleotide sequences.

Abstract: A process for recovering guanidine salts from diluted and contaminated aqueous solutions is described, wherein the corresponding aqueous solution (diluate) is subjected to electrodialysis and the guanidine salt is concentrated on the concentrate side. The corresponding guanidine salt can thus largely be separated from all contaminants while a relatively highly concentrated product is simultaneously obtained.