Phosphation tritylation

P-NMR spectroscopic studies on the reaction course of the dinucleotide synthesis from 3 -0-acetylthymidine 5 -phosphate (pT-Ac) (180a) and 5 -0-trityl-thymidine (Tr-T) in the presence of triisopropylbenzenesulfonyl chloride (TPS) confirm the metaphosphate hypothesis 123,124). Successive addition of 0.5 equiv. 

Abbreviations AllocOSu, allyloxycarbonyl-A-hydroxysuccinimide BCIP, 5-bromoA-chloro-3-indolyl Boc, tert-butyloxycarbonyl tBu, tert-butyl DCM, dichloromethane Dde, l-(4,4-dimethyl-2,6-dioxocyclohex-l-ylidene)ethyl Ddz, a, a-dimethyl-3,5-dimethoxyben-zyloxycarbonyl DIC, A,A -diisopropylcarbodiimide DIEA, A,fV-diisopropylethylamine DMF, iV,./V-dimethylformamide FmocOSu, 9-fluorenylmethyloxycarbonyl-AMiydroxysucci-nimide OBOC, one-bead one-compound PBS, phosphate-buffered saline Pmc, 2,2,5,7,8-pentamethylchroman-6-sulfonyl PTH, phenylthiohydantoin RR, relative reactivities Teoc, 2-(trimethylsilyl)ethoxycarbonyl TFA, trifluoroacetic acid Trt, trityl. 

Tris-(6-trityl-l,2-isopropylidene-D-glucofuranosyl) 3-phosphate amorphous -24.7 Me,CO 36... 

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