Identification of a series of substituted 2-piperazinyl-5-pyrimidylhydroxamic acids as potent histone deacetylase inhibitors.

Pursuing our efforts in designing 5-pyrimidylhydroxamic acid anti-cancer agents, we have identified a new series of potent histone deacetylase (HDAC) inhibitors. These compounds exhibit enzymatic HDAC inhibiting properties with IC(50) values in the nanomolar range and inhibit tumor cell proliferation at similar levels. Good solubility, moderate bioavailability, and promising in vivo activity in xenograft model made this series of compounds interesting starting points to design new potent HDAC inhibitors.

JNJ-26481585, a novel "second-generation" oral histone deacetylase inhibitor, shows broad-spectrum preclinical antitumoral activity.

Purpose: Histone deacetylase (HDAC) inhibitors have shown promising clinical activity in the treatment of hematologic malignancies, but their activity in solid tumor indications has been limited. Most HDAC inhibitors in clinical development only transiently induce histone acetylation in tumor tissue. Here, we sought to identify a "second-generation" class I HDAC inhibitor with prolonged pharmacodynamic response in vivo, to assess whether this results in superior antitumoral efficacy.

Impact on farnesyltransferase inhibition of 4-chlorophenyl moiety replacement in the Zarnestra series.

Based on the structure of R115777 (tipifarnib, Zarnestra), a series of farnesyltransferase inhibitors have been synthesized by modification of the 2-quinolinone motif and transposition of the 4-chlorophenyl ring to the imidazole or its replacement by 5-membered rings. This has yielded a novel series of potent farnesyltransferase inhibitors.

Discovery of pyrimidyl-5-hydroxamic acids as new potent histone deacetylase inhibitors.

A series of pyrimidyl-5-hydroxamic acids was prepared for evaluation as inhibitors of histone deacetylase (HDAC). Amino-2-pyrimidinyl can be used as a linker to provide HDAC inhibitors of good enzymatic potency.

Substituted azoloquinolines and -quinazolines as new potent farnesyl protein transferase inhibitors.

A series of (4-chlorophenyl)-alpha-(1-methyl-1H-imidazol-5-yl)azoloquinolines and -quinazolines was prepared. These compounds displayed potent Farnesyl Protein Transferase inhibitory activity and tetrazolo[1,5-a]quinazolines are promising agents for oral in vivo inhibition.

4-methyl-1,2,4-triazol-3-yl heterocycle as an alternative to the 1-methylimidazol-5-yl moiety in the farnesyltransferase inhibitor ZARNESTRA.

Replacement of the 1-methylimidazol-5-yl moiety in the farnesyltransferase inhibitor ZARNESTRA series by a 4-methyl-1,2,4-triazol-3-yl group gave us compounds with similar structure-activity relationship profiles showing that this triazole is potentially a good surrogate to imidazole for farnesyltransferase inhibition.

5-imidazolyl-quinolinones, -quinazolinones and -benzo-azepinones as farnesyltransferase inhibitors.

The evaluation of structure-activity relationships associated with the modification of the R115777 quinolinone ring moiety displaying potent in vitro inhibiting activity is described.