Christer Sahlberg

Urea-PETT compounds as a new class of HIV-1 reverse transcriptase inhibitors. 3. Synthesis and further structure-activity relationship studies of PETT analogues

The further development of allosteric HIV-1 RT inhibitors in the urea analogue series of PETT (phenylethylthiazolylthiourea) derivatives is described here. The series includes derivatives with an ethyl linker (1-5) and racemic (6-16) and enantiomeric (17-20) cis-cyclopropane compounds. The antiviral activity was determined both at the RT level and in cell culture on both wild-type and mutant forms of HIV-1. Most compounds have anti-HIV-1 activity on the wt in the nanomolar range. Resistant HIV-1 was selected in vitro for some of the compounds, and the time for resistant HIV-1 to develop was longer for urea-PETT compounds than it was for reference compounds. Preliminary pharmacokinetics in rats showed that compound 18 is orally bioavailable and penetrates well into the brain. The three-dimensional structure of complexes between HIV-1 RT and two enantiomeric compounds (17 and 18) have been determined. The structures show similar binding in the NNI binding pocket. The propionylphenyl moieties of both inhibitors show perfect stacking to tyrosine residues 181 and 188. The cyclopropyl moiety of the (+)-enantiomer 18 exhibits optimal packing distances for the interactions with leucine residue 100 and valine residue 179.

Synthesis and anti-HIV activities of urea-pETT analogs belonging to a new class of potent non-nucleoside HIV-1 Reverse transcriptase inhibitors

A series of potent specific HIV-1 RT inhibitory compounds is described. The compounds are urea analogs of PETT (PhenylEthylThiazoleThiourea) derivatives and the series includes derivatives with an ethyl linker (1-6) and conformationally restricted analogs (7-13). The antiviral activity is determined both at the RT level and in cell culture on both native and mutant forms of HIV-1. Many compounds display activity in the nM range against wt-RT.

Synthesis of conjugated dienes by nickel-catalyzed reactions of 1,3-alkadien-2-yl phosphates with grignard reagents

Abstract 2-Substituted 1,3-alkadienes were prepared in good yields by reactions of diethyl 1-methylene-2-propenyl phosphate and diethyl 1-methylene-3-phenyl-2-propenyl phosphate with various Grignard reagents in the presence of nickel(II) catalysts.

Synthesis of 3′-ethynylthymidine, 3′-vinylthymidine and 3′-bromovinylthymidine as potential antiviral agents

Abstract The synthesis of three novel 3′-unsaturated carbon analogues of AZT and FLT is described. The key step in the synthesis is a Cu(I)- catalyzed addition of vinylmagnesium bromide to a 2,3-unsaturated lactone, followed by, in the case of compounds 2 and 3 , elimination reactions of a dibromo-compound.

Design and synthesis of potent macrocyclic renin inhibitors.

Two types of P1-P3-linked macrocyclic renin inhibitors containing the hydroxyethylene isostere (HE) scaffold just outside the macrocyclic ring have been synthesized. An aromatic or aliphatic substituent (P3sp) was introduced in the macrocyclic ring aiming at the S3 subpocket (S3sp) in order to optimize the potency. A 5-6-fold improvement in both the K(i) and the human plasma renin activity (HPRA)IC(50) was observed when moving from the starting linear peptidomimetic compound 1 to the most potent macrocycle 42 (K(i) = 3.3 nM and HPRA IC(50) = 7 nM). Truncation of the prime side of 42 led to 8-10-fold loss of inhibitory activity in macrocycle 43 (K(i) = 34 nM and HPRA IC(50) = 56 nM). All macrocycles were epimeric mixtures in regard to the P3sp substituent and X-ray crystallographic data of the representative renin macrocycle 43 complex showed that only the S-isomer buried the substituent into the S3sp. Inhibitory selectivity over cathepsin D (Cat-D) and BACE-1 was also investigated for all the macrocycles and showed that truncation of the prime side increased selectivity of inhibition in favor of renin.

Allenes and acetylenes XXVI. Organocuprate reactions of 1,3-alkadien-2-yl phosphates. a new approach to the synthesis of allenes

Abstract Allenic hydrocarbons and one γ-allenic ketone were prepared in poor to good yields by the reactions of diethyl 1-methylene-2-propenyl phosphate and diethyl 1-(1-cyclohexenyl) phosphate with various organocuprates.

Mechanistic aspects of reductions of allylic ethers and acetates with organocuprates

Abstract The rate of substitution to reduction has been investigated for reactions of three phenyl-substituted allylic ethers and the corresponding acetates with EtMgBr plus 10 or 25% copper(I) bromide in THF. It is found that the relative amount of reduction increases with increased electron delocalization in the postulated copper(III)-bound allyl ligand, and is also dependent on the nature of the leaving group; methoxy giving much more reduction product than acetoxy. Furthermore, for one acetate investigated there was more reduction at −65° than at −25°C. The results are interpreted in terms of relative binding strength of allyl ligands to a copper(III) intermediate.

Allenes and acetylenes XVII. Allenic amines from organocuprate reactions

Aus den Acetylen-aminen (I) entstehen mit Butylmagnesiumbromid in Gegenwart von CuJ die Allenyl-Verbindungen (II), die zu Allen-aminen (III) hydrolysiert werden.