Arachidonylsulfonyl derivatives as cannabinoid CB1 receptor and fatty acid amide hydrolase inhibitors

Synthesis and biological evaluation of novel irreversible serine protease inhibitors using amino acid based sulfonyl fluorides as an electrophilic trap

We have designed and synthesized novel irreversible serine protease inhibitors containing aliphatic sulfonyl fluorides as an electrophilic trap. These substituted taurine sulfonyl fluorides derived from taurine or protected amino acids were conveniently synthesized from β-aminoethanesulfonyl chlorides using KF/18-crown-6 or from β-aminoethanesulfonates using DAST. Their potency of irreversible inhibition of serine proteases is described in different enzyme assays using chymotrypsin leading to binding affinities up to 22 μM.

Microwave Assisted Synthesis of Sodium Sulfonates Precursors of Sulfonyl Chlorides and Fluorides

We describe the use of a microwave reaction for the conversion of various bromides to sodium sulfonates that have been further elaborated to sulfonyl chlorides. This new approach leads to much improved yields and shorter reaction times. Representative sulfonyl chlorides serve as precursors for the respective sulfonyl fluorides that are potent inhibitors of the fatty acid amide hydrolase.

Discovery of boronic acids as novel and potent inhibitors of fatty acid amide hydrolase

A series of commercial phenyl-, heteroaryl-, alkyl-, and alkenylboronic acids were evaluated for their FAAH and MGL inhibitory activities. The compounds were generally selective for FAAH, with IC50 in the nanomolar or low-micromolar range. Eight of these compounds inhibited MGL with IC50 in the micromolar range. The most potent compound, phenylboronic acid with para-nonyl substituent (13), inhibited FAAH and MGL with IC50 of 0.0091 and 7.9 microM, respectively.

Fatty acid amide hydrolase: a gate-keeper of the endocannabinoid system

The family of endocannabinoids contains several polyunsaturated fatty acid amides such as anandamide (AEA), but also esters such as 2-arachidonoylglycerol (2-AG). These compounds are the main endogenous agonists of cannabinoid receptors, able to mimic several pharmacological effects of Delta9-tetrahydrocannabinol (Delta9-THC), the active principle of Cannabis sativa preparations like hashish and marijuana. The activity of AEA at its receptors is limited by cellular uptake, through a putative membrane transporter, followed by intracellular degradation by fatty acid amide hydrolase (FAAH). Growing evidence demonstrates that FAAH is the critical regulator of the endogenous levels of AEA, suggesting that it may serve as an attractive therapeutic target for the treatment of human disorders. In particular, FAAH inhibitors may be next generation therapeutics of potential value for the treatment of pathologies of the central nervous system, and of peripheral tissues. Investigations into the structure and function of FAAH, its biological and therapeutic implications, as well as a description of different families of FAAH inhibitors, are the topic of this chapter.

Further advances in the synthesis of endocannabinoid-related ligands

Recent advances in the synthesis of endocannabinoid-related ligands for the period 2001-2004 are covered in this review. During this period the first solid phase synthesis of anandamide (AEA) analogs was developed, which allows modification at both the head group and the end pentyl chain. Synthesis of water-soluble prodrugs of noladin ether was reported, which are chemically stable, rapidly release noladin ether under enzymatic conditions and are shown to reduce intraocular pressure. The structure-activity relationships (SAR) of alkylcarbamic acid aryl esters and the discovery of potent archidonylsulfonyl derivatives as fatty acid amide hydrolase (FAAH) inhibitors are summarized. Recent synthetic developments in the controversial area of anandamide membrane transporter (AMT) inhibitors are also discussed.