1. New approaches to the industrial synthesis of HIV protease inhibitors
Yutaka Honda, Satoshi Katayama, Mitsuhiko Kojima, Takayuki Suzuki, Naomi Kishibata and Kunisuke Izawa *. Org. Biomol. Chem., 2004, 2, 2061–2070
We have described here new processes that may be suitable for the industrial-scale synthesis of the intermediates of the HIV protease inhibitors Amprenavir/Fosamprenavir (developed by Vertex-GlaxoSmithKline). To prepare the optically active side chain, a new approach to 3-hydroxytetra-hydrofuran from commonly available malic acid has been established. By combining this with our method for halomethyl ketone synthesis, several routes to the precursor of Amprenavir were investigated. Synthetic processes that involve safe and practical reactions with readily available raw materials were realized. The process in which the tetrahydrofuranyloxy carbonyl group is installed at an early stage, without using common protecting groups, was quite efficient and may have real industrial potential.
2. Discovery of GS-8374, a potent human immunodeficiency virus type 1 protease inhibitor with a superior resistance profile
Gong-Xing He, Zheng-Yu Yang, Lianhong Xu*. Med. Chem. Commun., 2011, 2, 1093–1098
In our multi-pronged approach in searching for novel HIV-1 PIs, we observed that the incorporation of polar moieties at the P1 site of a PI can improve the resistance profile of a parent PI scaffold and thus render it to be active against several multidrug-resistant variants of HIV-1 such as the I84V/L90M mutant. Among the approved HIV-1 PIs, the peptidomimetic bis-tetra-hydrofuran sulfonamide analog DRV (2), possesses arguably the most favorable resistance profile. We pursued further optimi-zation of the antiviral potency, activity against PI-resistant HIV-1 variants, as well as other pharmacological properties. HIV-1 strains with high level PI resistance containing M46I/I50V or I84V/L90M mutations in protease were selected for the first tier resistance profiling of the new analogs. M46I/I50V mutant virus was selectedin vitroin the presence of amprenavir, and the I84V/L90M variant is a patient-derived recombinant strain exhibiting markedly reduced susceptibility to all tested PIs, except DRV. Both HIV-1 variants also show residual resistance to the pepti-domimetic bis-tetrahydrofuran sulfonamide class of PIs.