Improved Industrial Syntheses of Penciclovir and Famciclovir Using N2-Acetyl-7-Benzylguanine and a Cyclic Side Chain Precursor
We have established practical synthetic methods for penciclovir (PCV, 1) and famciclovir (FCV, 2) from N2-acetyl-7-benzylguanine (NAc7BnG, 3) and 6,6-dimethyl-5, 7-dioxaspiro[2.5]octane-4,8-dione (4)--the latter being a more easily prepared cyclic precursor of the diacetate side chain (5) used in the conventional process. The coupling of 4 with 3 proceeded regioselectively at the N9 position of guanine in good yield. The coupling product was then successfully transformed into the known antiviral agents in a short number of steps.
Available from: 126.96.36.199
[Show abstract] [Hide abstract]
ABSTRACT: A new expeditious method for the homo-conjugate addition of nitrogen heteroaromatics to 1,1-cyclopropanedicarboxylates was developed in the presence of La(OTf)3 as an efficient Lewis acid catalyst under microwave irradiation.
Tetrahedron Letters 10/2008; 49(41). DOI:10.1016/j.tetlet.2008.07.142 · 2.38 Impact Factor
Bioactive Heterocyclic Compound Classes, 03/2013: pages 217-236; , ISBN: 9783527333950
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.