77141-07-2

Fmoc-N,N′-Bis-Boc-7-guanyl-Tic-OH (GTIC), a conformationally constrained amino acid with basic properties, has been synthesized in four steps. This amino acid can be incorporated into peptides using standard Fmoc solid phase synthesis, and to test its potential for biological activity applications, we prepared an analog of H-Dmt-Tic-NH2.

A series of 17-cyclopropylmethyl-3,14β-dihydroxy-4,5α-epoxy-6α-(isoquinoline-3′-carboxamido)morphinan (NAQ) analogues were synthesized and pharmacologically characterized to study their structure-activity relationship at the mu opioid receptor (MOR). The competition binding assay showed two-atom spacer and aromatic side chain were optimal for MOR selectivity. Meanwhile, substitutions at the 1′- and/or 4′-position of the isoquinoline ring retained or improved MOR selectivity over the kappa opioid receptor while still possessing above 20-fold MOR selectivity over the delta opioid receptor. In contrast, substitutions at the 6′- and/or 7′-position of the isoquinoline ring reduced MOR selectivity as well as MOR efficacy. Among this series of ligands, compound 11 acted as an antagonist when challenged with morphine in warm-water tail immersion assay and produced less significant withdrawal symptoms compared to naltrexone in morphine-pelleted mice. Compound 11 also antagonized the intracellular Ca2+ increase induced by DAMGO. Molecular dynamics simulation studies of 11 in three opioid receptors indicated orientation of the 6′-nitro group varied significantly in the different 'address' domains of the receptors and played a crucial role in the observed binding affinities and selectivity. Collectively, the current findings provide valuable insights for future development of NAQ-based MOR selective ligands.

Disclosed are promoieties of the following formula which can be used to form prodrugs of nitrogen-containing or hydroxyl-containing drug or a pharmaceutically active agent: (I) and pharmaceutical compositions comprising the prodrugs.

Compounds of formula (I) are inhibitors of histone deacetylase activity, and are useful in the treatment of, for example, cancers, wherein R1 is a carboxylic acid group (-COOH), or an ester group which is hydrolysable by one or more intracellular carboxyesterase enzymes to a carboxylic acid group; R2is the side chain of a natural or non-natural alpha amino acid; Y is a bond, -C(=O)-, -S(=O)2-, -C(=O)O-, -C(O)NR3-, -C(=S)-NR3 , -C(=NH)NR3 or -S(=O)2NR3- wherein R3 is hydrogen or optionally substituted C1-C6 alkyl; L1 is a divalent radical of formula -(Alk1)m(Q)n(Alk2)p- wherein m, n and p are independently 0 or 1 , Q is (i) an optionally substituted divalent mono- or bicyclic carbocyclic or heterocyclic radical having 5 - 13 ring members, or (ii), in the case where both m and p are 0, a divalent radical of formula -X2-Q1- or -Q1-X2- wherein X2 is -O-, S- or NRA- wherein RA is hydrogen or optionally substituted C1-C3 alkyl, and Q1 is an optionally substituted divalent mono- or bicyclic carbocyclic or heterocyclic radical having 5 - 13 ring members, AIk1 and AIk2 independently represent optionally substituted divalent C3-C7 cycloalkyl radicals, or optionally substituted straight or branched, C1-C6 alkylene, C2-C6 alkenylene ,or C2-C6 alkynylene radicals which may optionally contain or terminate in an ether (-O-), thioether (-S-) or amino (-NRA-) link wherein RA is hydrogen or optionally substituted C1-C3 alkyl; X1 represents a bond; -C(=O); or -S(=O)2-; -NR4C(=O)-, -C(=O)NR4-, -NR4C(=O)NR5- , -NR4S(=O)2-, or -S(=O)2NR4-wherein R4 and R5 are independently hydrogen or optionally substituted C1-C6 alkyl; z is 0 or 1 ; A represents an optionally substituted mono-, bi- or tri-cyclic carbocyclic or heterocyclic ring system wherein the radicals R1R2NH-Y-L1-X1-[CH2]Z- and HONHCO-[LINKER]- are attached different ring atoms; and -[Linker]- represents a divalent linker radical linking a ring atom in A with the hydroxamic acid group CONHOH, the length of the linker radical, from the terminal atom linked to the ring atom of A to the terminal atom linked to the hydroxamic acid group, is equivalent to that of an unbranched saturated hydrocarbon chain of from 3-10 carbon atoms.

High-throughput screening of the P&GP corporate repository against several protein tyrosine phosphatases identified the sulfamic acid moiety as potential phosphotyrosine mimetic. Incorporation of the sulfamic acid onto a 1,2,3,4-tetrahydroisoquinoline sca