The pyrrolo[2,1-f][1,2,4]triazine nucleus was identified as a novel kinase inhibitor template which effectively mimics the well-known quinazoline kinase inhibitor scaffold. Attachment of a 4-((3-chloro-4-fluorophenyl)amino) substituent to the template provided potent biochemical inhibitors of the tyrosine kinase activity of EGFR, as well as inhibition of cellular proliferation of the human colon tumor cell line DiFi. Attachment of a 4-((3-hydroxy-4-methylphenyl)amino) substituent provided potent inhibitors of VEGFR-2 which also showed effects on the VEGF-dependent proliferation of human umbilical vein endothelial cells. Biological activity was maintained with substitution at positions 5 or 6, but not 7, suggesting that the former positions are promising sites for introducing side chains which modulate physicochemical properties. Preliminary inhibition studies with varying ATP concentrations suggest that, like the quinazoline-based kinase inhibitors, the pyrrolotriazine-based inhibitors bind in the ATP pocket.

A series of novel amide-based small molecule inhibitors of inosine monophosphate dehydrogenase (IMPDH) was explored. The synthesis and the structure–activity relationships (SARs) derived from in vitro studies are described.

High throughput screening identified 2-acetamido-thiazolylthio acetic ester 1 as an inhibitor of cyclin-dependent kinase 2 (CDK2). Because this compound is inactive in cells and unstable in plasma, we have stabilized it to metabolic hydrolysis by replacing the ester moiety with a 5-ethyl-substituted oxazole as in compound 14. Combinatorial and parallel synthesis provided a rapid analysis of the structure-activity relationship (SAR) for these inhibitors of CDK2, and over 100 analogues with IC50 values in the 1-10 nM range were rapidly prepared. The X-ray crystallographic data of the inhibitors bound to the active site of CDK2 protein provided insight into the binding modes of these inhibitors, and the SAR of this series of analogues was rationalized. Many of these analogues displayed potent and broad spectrum antiproliferative activity across a panel of tumor cell lines in vitro. In addition, A2780 ovarian carcinoma cells undergo rapid apoptosis following exposure to CDK2 inhibitors of this class. Mechanism of action studies have confirmed that the phosphorylation of CDK2 substrates such as RB, histone H1, and DNA polymerase alpha (p70 subunit) is reduced in the presence of compound 14. Further optimization led to compounds such as water soluble 45, which possesses a favorable pharmacokinetic profile in mice and demonstrates significant antitumor activity in vivo in several murine and human models, including an engineered murine mammary tumor that overexpresses cyclin E, the coactivator of CDK2.

Continuing structure-activity studies were performed on the 2,3,4,5-tetrahydro-1-(imidazol-4-ylalkyl)-1,4-benzodiazepine farnesyltransferase (FT) inhibitors. These studies demonstrated that; a 3(R)-phenylmethyl group, a hydrophilic 7-cyano group, and a 4-sulfonyl group bearing a variety of substituents provide low;nanomolar FT inhibitors with cellular activity at concentrations below 100 nM. Maximal in vivo activity in the mutated K-Ras bearing HCT-116 human colon tumor model was achieved with analogues carrying hydrophobic side chains such as propyl, phenyl, or thienyl attached to the N-4 sulfonyl group. Several such compounds achieved curative efficacy when given orally in this model. On the basis of its excellent preclinical antitumor activity and promising pharmacokinetics, compound 20 (BMS-214662, (R)-7-cyano-2;3,4,5-tetrahydro-1-(1H-imidazol-4-ylmethyl)-3-(phenylmethyl)-4-(2-thienylsulfonyl)- -1H-1,4-benzodiazepine) has been advanced into human clinical trials.

2,3,4,5-Tetrahydro-1-(imidazol-4-ylalkyl)-1,4-benzodiazepines were found to be potent inhibitors of farnesyltransferase (FT). A hydrophobic substituent at the 4-position of the benzodiazepine, linked via a hydrogen bond acceptor, was important to enzyme inhibitory activity. An aryl ring at position 7 or a hydrophobic group linked to the 8-position through an amide, carbamate, or urea linkage was also important for potent inhibition. 2,3,4, 5-Tetrahydro-1-(1H-imidazol-4-ylmethyl)-7-(4-pyridinyl)-4-[2-(t rifluo romethoxy)benzoyl]-1H-1,4-benzodiazepine (36), with an FT IC(50) value of 24 nM, produced 85% phenotypic reversion of Ras transformed NIH 3T3 cells at 1.25 microM and had an EC(50) of 160 nM for inhibition of anchorage-independent growth in soft agar of H-Ras transformed Rat-1 cells. Selected analogues demonstrated ip antitumor activity against an ip Rat-1 tumor in mice.

A practical synthesis of the antiviral agent lobucavir, [1R(1 alpha,2 beta,3 alpha)] -2-amino-9-[2,3-bis(hydroxymethyl)cyclobutyl]-6H-purin-6-one (BMS-180194), is described. The key chiral intermediate, [1S-(1 alpha,2 beta,3 alpha)]-3-hydroxy-1,2-cyclobutanedimethanol, dihenzoate ester, was made by an asymmetric [2 + 2] cycloaddition of dimenthyl fumarate with ketene dimethyl acetal followed by sequential diester reduction, benzoylation, deketalization, and stereoselective ketone reduction. Regioselective N9-alkylation of the tetra-n-butylammonium salt of 2-amino-6-iodopurine with the derived cyclobutyltriflate furnished the purinecyclobutyl dibenzoate. Methanolysis followed by acid hydrolysis produced lobucavir in a 35% overall yield with an ee, 99%.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A series of HIV protease inhibitors containing a novel C2 symmetrical "aminodiol" core structure were prepared from amino acid starting materials. The ability of the aminodiols to inhibit HIV replication in cell culture is comparable to their ability to inhibit the isolated enzyme, a result compatible with good cell membrane penetration by this class of compounds. Optimization of the structure-activity in this series led to aminodiol 9a (Ki = 100 nM; ED50 (HIV-1) = 80 nM) containing P1/P1 benzyl and P2/P2 Boc substituents. Compound 9a is a selective inhibitor of HIV protease versus other aspartyl proteases such as human renin, human cathepsin D, and porcine pepsin. In addition, 9a is equipotent against HIV-1 and HIV-2 in cell culture and demonstrates similar activity in infected T-lymphocytes and PBMCs. After i.v. and oral administration in rats, 9a displayed significant oral bioavailability (ca. 40%) and a promising plasma elimination half-life (4 h).

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The syntheses of the enantiomeric cyclobutyl guanine nucleoside analogues [1R-1 alpha, 2 beta, 3 alpha]- and [1S-1 alpha, 2 beta, 3 alpha]-2- amino-9-[2,3-bis(hydroxymethyl)cyclobutyl]-6H-purin-6-one (7 and 8, respectively) and the enantiomeric cyclobutyl adenine analogues [1R-1 alpha, 2 beta, 3 alpha]- and [1S-1 alpha, 2 beta, 3 alpha]-6-amino-9-[2,3-bis(hydroxymethyl) cyclobutyl]purine (9 and 10, respectively) are described. trans-3,3-Diethoxy-1,2-cyclobutanedicarboxylic acid (14) was coupled with R-(-)-2-phenylglycinol to provide a mixture of diastereomeric bis-amides, 15a and 15b, which was readily separated by crystallization. Conversion of each bis-amide to the corresponding diol enantiomer, 16a and 16b, respectively, was effected by a facile three-step sequence in high overall yield. Homochiral diol 16a was converted in a straightforward manner to 7 and 9, and homochiral diol 16b was similarly converted to the corresponding optical isomers 8 and 10. Compounds 7 and 9, which mimic the absolute configuration of natural nucleosides, are highly active against a range of herpesviruses in vitro while the isomers of opposite configuration, 8 and 10, are devoid of antiherpes activity. The corresponding triphosphates of 7 and 8 (7-TP and 8-TP) were prepared enzymatically. Compound 7-TP selectively inhibits HSV-1 DNA polymerase, compared to human (HeLa) DNA polymerase, while 8-TP is much less inhibitory than 7-TP against both types of enzymes. Compounds 7 and 9 are efficacious in a mouse cytomegalovirus model infection.

ChemInformVolume 20, Issue 5 Natural Products ChemInform Abstract: Total Synthesis of Pseudomonic Acid C (I). J. C. BARRISH, J. C. BARRISH Chem. Res. Dep., Hoffmann-La Roche, Inc., Nutley, NJ 07110, USASearch for more papers by this authorH. L. LEE, H. L. LEE Chem. Res. Dep., Hoffmann-La Roche, Inc., Nutley, NJ 07110, USASearch for more papers by this authorT. MITT, T. MITT Chem. Res. Dep., Hoffmann-La Roche, Inc., Nutley, NJ 07110, USASearch for more papers by this authorG. PIZZOLATO, G. PIZZOLATO Chem. Res. Dep., Hoffmann-La Roche, Inc., Nutley, NJ 07110, USASearch for more papers by this authorE. G. BAGGIOLINI, E. G. BAGGIOLINI Chem. Res. Dep., Hoffmann-La Roche, Inc., Nutley, NJ 07110, USASearch for more papers by this authorM. R. USKOKOVIC, M. R. USKOKOVIC Chem. Res. Dep., Hoffmann-La Roche, Inc., Nutley, NJ 07110, USASearch for more papers by this author J. C. BARRISH, J. C. BARRISH Chem. Res. Dep., Hoffmann-La Roche, Inc., Nutley, NJ 07110, USASearch for more papers by this authorH. L. LEE, H. L. LEE Chem. Res. Dep., Hoffmann-La Roche, Inc., Nutley, NJ 07110, USASearch for more papers by this authorT. MITT, T. MITT Chem. Res. Dep., Hoffmann-La Roche, Inc., Nutley, NJ 07110, USASearch for more papers by this authorG. PIZZOLATO, G. PIZZOLATO Chem. Res. Dep., Hoffmann-La Roche, Inc., Nutley, NJ 07110, USASearch for more papers by this authorE. G. BAGGIOLINI, E. G. BAGGIOLINI Chem. Res. Dep., Hoffmann-La Roche, Inc., Nutley, NJ 07110, USASearch for more papers by this authorM. R. USKOKOVIC, M. R. USKOKOVIC Chem. Res. Dep., Hoffmann-La Roche, Inc., Nutley, NJ 07110, USASearch for more papers by this author First published: January 31, 1989 https://doi.org/10.1002/chin.198905313AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume20, Issue5January 31, 1989 RelatedInformation

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTotal synthesis of pseudomonic acid CJoel C. Barrish, Hsi Lin Lee, Toomas Mitt, Giacomo Pizzolato, Enrico G. Baggiolini, and Milan R. UskokovicCite this: J. Org. Chem. 1988, 53, 18, 4282–4295Publication Date (Print):September 1, 1988Publication History Published online1 May 2002Published inissue 1 September 1988https://pubs.acs.org/doi/10.1021/jo00253a021https://doi.org/10.1021/jo00253a021research-articleACS PublicationsRequest reuse permissionsArticle Views1388Altmetric-Citations41LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

Synthese a partir de L-arabinose, par l'intermediaire de l'anhydro-3,4 didesoxy-2,6 α-L-ribo-hexopyranoside de methyle