Showing papers by "Pierre L. Beaulieu published in 1996"

Preparation of Aminoalkyl Chlorohydrin Hydrochlorides: Key Building Blocks for Hydroxyethylamine-Based HIV Protease Inhibitors

Abstract: Enantiomerically pure N,N-dibenzyl-α-amino aldehydes reacted with (chloromethyl)lithium, generated in situ from bromochloromethane and lithium metal, to give predominantly erythro aminoalkyl epoxides. Treatment of the crude epoxides with aqueous hydrochloric acid gave crystalline (2S,3S)-N,N-dibenzylamino chlorohydrin hydrochlorides in 32−56% overall yield and high isomeric purity. These compounds are versatile synthetic intermediates for the preparation of hydroxyethylamine-based HIV protease inhibitors, either directly as such, or via conversion to the corresponding N-Boc-(2S,3S)-aminoalkyl epoxides. The processes described do not make use of hazardous reagents or intermediates, do not require chromatographic purifications, and are thus amenable to the preparation of large quantities of these versatile building blocks.

Peptidomimetic inhibitors of herpes simplex virus ribonucleotide reductase with improved in vivo antiviral activity

Abstract: We have been investigating the potential of a new class of antiviral compounds. These peptidomimetic derivatives prevent association of the two subunits of herpes simplex virus (HSV) ribonucleotide reductase (RR), an enzyme necessary for efficient replication of viral DNA. The compounds disclosed in this paper build on our previously published work. Structure-activity studies reveal beneficial modifications that result in improved antiviral potency in cell culture in a murine ocular model of HSV-induced keratitis. These modifications include a stereochemically defined (2,6-dimethylcyclohexyl)amino N-terminus, two ketomethylene amide bond isosteres, and a (1-ethylneopentyl)amino C-terminus. These three modifications led to the preparation of BILD 1351, our most potent antiherpetic agent containing a ureido N-terminus. Incorporation of the C-terminal modification into our inhibitor series based on a (phenylpropionyl)valine N-terminus provided BILD 1357, a significantly more potent antiviral compound than our previously published best compound, BILD 1263.

Ureido-Based Peptidomimetic Inhibitors of Herpes Simplex Virus Ribonucleotide Reductase: An Investigation of Inhibitor Bioactive Conformation

Abstract: We have been investigating peptidomimetic inhibitors of herpes simplex virus (HSV) ribonucleotide reductase (RR). These inhibitors bind to the HSV RR large subunit and consequently prevent subunit association and subsequent enzymatic activity. This report introduces a new series of compounds that contain an extra nitrogen (a ureido function) at the inhibitor N-terminus. This nitrogen improves inhibitor binding potency 50-fold over our first published inhibitor series. Evidence supports that this improvement in potency results from a new hydrogen-bonding contact between the inhibitor and the RR large subunit. This report also provides evidence for the bioactive conformation around two important amino acid residues contained in our inhibitors. A tert-butyl group, which contributes 100-fold to inhibitor potency but does not directly bind to the large subunit, favors an extended β-strand conformation that is prevalent in solution and in the bound state. More significantly, the bioactive conformation around a ...

Protease inhibiting succinic acid derivatives

Abstract: Disclosed herein are compounds which inhibit human immunodeficiency virus (HIV) protease activity and inhibit HIV replication in human cells Thus, the compounds are indicated for the treatment of HIV infections The compounds can be represented by formula (I), wherein X is a terminal group, for example, an aryloxycarbonyl, an alkanoyl or an arylalkyl carbamoyl; A is absent or an amino acid or a derived amino acid; either R1 or R2 is hydrogen while the other is alkyl or R?1 and R2? are joined to form a cyclohexane; Q is hydrogen, hydroxy, halo or lower alkoxy; and Y is a terminal group, for example, an alkylamino, alkoxy or an optionally substituted anilino

Preparation of Aminoalkyl Chlorohydrin Hydrochlorides: Key Building Blocks for Hydroxyethylamine-Based HIV Protease Inhibitors.

Abstract: Enantiomerically pure N,N-dibenzyl-α-amino aldehydes reacted with (chloromethyl)lithium, generated in situ from bromochloromethane and lithium metal, to give predominantly erythro aminoalkyl epoxides. Treatment of the crude epoxides with aqueous hydrochloric acid gave crystalline (2S,3S)-N,N-dibenzylamino chlorohydrin hydrochlorides in 32−56% overall yield and high isomeric purity. These compounds are versatile synthetic intermediates for the preparation of hydroxyethylamine-based HIV protease inhibitors, either directly as such, or via conversion to the corresponding N-Boc-(2S,3S)-aminoalkyl epoxides. The processes described do not make use of hazardous reagents or intermediates, do not require chromatographic purifications, and are thus amenable to the preparation of large quantities of these versatile building blocks.