Oximes conjugates

Ruthenium has been incorporated into ODNs, via an oxime conjugate,or through an amide linker. In the latter case, the ruthenium conjugate was used to photo-crosslink with a G residue on a complementary strand. Ruthenium and osmium have been incorporated into ODNs via a C5-phenanthroline dU amidite to study photoinduced energy transfer, and metallocarboranes have been used as redox labels by attachment to 04 of dT. Ferrocene has... 

Chemo-enzymatic synthesis with oxime conjugation... 

Fig. 27 Enzymatic introduction of sialic acid and C-7/8 chemical oxidation to aldehyde for oxime conjugation. ...

Fig. 28 Enzymatic introduction of ketone for oxime conjugation by glyco ltransferases. ...

Imines and oximes Aliphatic a,/3-Unsaturated and aromatic Conjugated cyclic systems 1690-1640 (w) 1650-1620 (m) 1660-1480 (var) 960-930 (s) NO stretching of oximes... 

An a-oximino enamine was formed by the reaction of nitrosyl chloride and triethylamine with morpholinocyclohexene 494). Oxime functions have also been introduced into carbonyl conjugated enamines with isoamyl nitrite or NjOj 495). 

The conjugate bases of nitro compounds (formed by treatment of the nitro compound with BuLi) react with Grignard reagents in the presence of C1CH= NMe Cr to give oximes RCH =N(0)0Li + R MgX RR C=NOH. ... 

Anthracenecarbonitrile oxide, prepared directly from 9-anthracenecarbald-oxime and N-chlorosuccinimide, reacts with dimethyl acetylenedicarboxylate to afford dimethyl 3-(9/-anthracenyl)isoxazole-4,5-dicarboxylate in good yield. Double activation reactions between this diester and hydrogenated lexitropsin 430, in a 1 2 molar ratio, produce a novel intercalating isoxazolyl bis-lexitropsin conjugate 431 as the major product (43). 

The sequential intramolecular conjugate addition of the oxime followed by intramolecular dipolar cycloaddition of the intermediate nitrone affords a... 

For example, the reaction of lithium diisopropylamine (82) with N-oxide (134) leads to a rather selective deprotonation at the C-4 atom (Scheme 3.111, Eq. 1). An analogous transfer of double bond was observed for six-membered cyclic nitronates 135 (Eq. 2) (143). However, intermediates (136) that formed in the latter case undergo fast fragmentation and give conjugated ene-oximes (137) as the final products. 

These enoximes can be prepared through available annelated six-membered cyclic nitronates (391) by their silylation giving rise to the iminium cations A, whose deprotonation affords annelated 2H-5,6-dihydrooxazines (392). After the known retro-fragmentation (490), the latter compounds are transformed into the target conjugated en oximes (395). 

N,C Elimination The reactions of standard BENAs with bases were considered in the previous section. As a rule, these reactions proceed at the silicon atom of the nitroso acetal fragment. However, if a EWG-group is adjacent to the y-C atom of BENA, the ally lie proton (Hy) at this carbon atom becomes so labile that it can be eliminated already in the presence of bases at room temperature (504), thus initiating the transformation of such BENA into conjugated en oximes (Scheme 3.227). 

In this modification, the radical C,C-coupling reaction is initiated by the addition of the initiator V-70, which evidently generates the OSiPli2Bu radical from the specially prepared BENA (500). Under the reaction conditions, the latter radical is rearranged into the Si(OPh)PhBu radical (529), which can cause growth of the chain as shown in Scheme 3.259. The product of this C,C-coupling is a functionalized conjugated ene oxime (501). 

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