1375082-86-2

Upstream product

• 15715-58-9 triethylamine carbonate 
• 1375142-33-8 (2S)-2-({[chloro(phosphono)methyl](hydroxy)phosphoryl}oxy)-2-phenylacetic acid 

Relevant academic research and scientific papers

Completing the β,γ-CXY-dNTP Stereochemical probe toolkit: Synthetic access to the dCTP diastereomers and 31P and 19F NMR correlations with absolute configurations

Nucleoside 5′-triphosphate (dNTP) analogues in which the β,γ-oxygen is mimicked by a CXY group (β,γ-CXYdNTPs) have provided information about DNA polymerase catalysis and fidelity. Definition of CXY stereochemistry is important to elucidate precise binding modes. We previously reported the (R)- and (S)-β,γ-CHX-dGTP diastereomers (X = F, Cl), prepared via P,C-dimorpholinamide CHCl (6a, 6b) and CHF (7a, 7b) bisphosphonates (BPs) equipped with an (R)-mandelic acid as a chiral auxiliary, with final deprotection using H2/Pd. This method also affords the β,γ-CHCl-dTTP (11a, 11b), β,γ-CHF (12a, 12b), and β,γ-CHCl (13a, 13b) dATP diastereomers as documented here, but the reductive deprotection step is not compatible with dCTP or the bromo substituent in β,γ-CHBr-dNTP analogues. To complete assembly of the toolkit, we describe an alternative synthetic strategy featuring ethylbenzylamine or phenylglycine-derived chiral BP synthons incorporating a photolabile protecting group. After acid-catalyzed removal of the (R)-(+)-α-ethylbenzylamine auxiliary, coupling with activated dCMP and photochemical deprotection, the individual diastereomers of β,γ-CHBr- (33a, 33b), β,γ-CHCl- (34a, 34b), β,γ-CHF-dCTP (35a, 35b) were obtained. The β,γ-CH(CH3)-dATPs (44a, 44b) were obtained using a methyl (R)-(-)-phenylglycinate auxiliary. 31P and 19F NMR Δδ values are correlated with CXY stereochemistry and pKa2-4 values for 13 CXY-bisphosphonic acids and imidodiphosphonic acid are tabulated.

β,γ-CHF- and β,γ-CHCl-dGTP diastereomers: Synthesis, discrete 31P NMR signatures, and absolute configurations of new stereochemical probes for DNA polymerases

Deoxynucleoside 5′-triphosphate analogues in which the β,γ-bridging oxygen has been replaced with a CXY group are useful chemical probes to investigate DNA polymerase catalytic and base-selection mechanisms. A limitation of such probes has been that conventional synthetic methods generate a mixture of diastereomers when the bridging carbon substitution is nonequivalent (X ≠ Y). We report here a general solution to this long-standing problem with four examples of β,γ-CXY dNTP diastereomers: (S)- and (R)-β,γ-CHCl-dGTP (12a-1/12a-2) and (S)- and (R)-β,γ-CHF-dGTP (12b-1/12b-2). Central to their preparation was conversion of the prochiral parent bisphosphonic acids to the P,C-dimorpholinamide derivatives 7 of their (R)-mandelic acid monoesters, which provided access to the individual diastereomers 7a-1, 7a-2, 7b-1, and 7b-2 by preparative HPLC. Selective acidic hydrolysis of the P-N bond then afforded portal diastereomers, which were readily coupled to morpholine-activated dGMP. Removal of the chiral auxiliary by H2 (Pd/C) gave the four individual diastereomeric nucleotides 12, which were characterized by 31P, 1H, and 19F NMR spectroscopy and by mass spectrometry. After treatment with Chelex-100 to remove traces of paramagnetic ions, at pH ～10 the diastereomer pairs 12a,b exhibit discrete Pα and Pβ31P resonances. The more upfield Pα and more downfield Pβ resonances (and also the more upfield 19F NMR resonance in 12b) are assigned to the R configuration at the Pβ-CHX-P γ carbons on the basis of the absolute configurations of the individual diastereomers as determined from the X-ray crystallographic structures of their ternary complexes with DNA and polymerase β.