Synthesis and inhibitory activities against aminopeptidase B and enkephalin-degrading enzymes of ketomethylene dipeptide analogues of arphamenines.

Three ketomethylene pseudodideptide analogues [(S)Lys psi(COCH2)(R and S)Phe (14 or 15 and 15 or 14) and (S)Lys psi(COCH2)(xi Trp (19)] of natural arphamenine A [(S)Arg psi(COCH2(R,S)Phe (1)] were easily prepared by a route involving two successive main reactions: a malonic ester alkylation with Z-protected lysine iodomethyl ketone and the introduction of a benzyl or (indol-3-yl)methyl moiety in position 2 of the resulting 4-ketodiester. The isomer of 1 with reversed sequence, (S)Phe psi(COCH2)(R,S)Arg (22) was synthesized by guanidylation and subsequent deprotection of Z-(S)Phe psi(COCH2)(R,S)Orn. The inhibitory effects of compounds 14, 15, 19, and 22, and the related ketomethylene dipeptides (S)Ala psi(COCH2)(R,S)Phe (3), (S)Phe psi(COCH2)(R,S)X [X = Ala (4), Orn (5)] and (S)Trp psi(COCH2)(R,S)Y [Y = Orn (6), Lys (7), Arg (8)] on aminopeptidase B (AP-B), and enkephalin-degrading enzymes [aminopeptidase N (APN) and neutral endopeptidase (NEP)] were compared with that of the model compound 1.     

R-1579类似物的合成及其二肽基肽酶IV(DPP-IV)抑制活

目的 设计合成R-1579的类似物,并对其体外DPP-IV抑制活性进行评价。方法 以取代苯甲醛和丙二腈为原料经缩合、与脒环合、氧化及催化氢化等反应制得目标化合物;选择其中部分化合物测试其DPP-IV抑制活性。结果与结论 共制得18个目标化合物,经过1H-NMR、MS确证结构,其中化合物8h、10c及10d的活性优于阳性对照R-1579。     

吡考他胺结构类似物的合成及其抗血小板聚集活性研究

目的通过对抗血小板聚集药物picotamide(吡考他胺)分子的1,3-侧链进行结构修饰和改造来合成新的类似物,以期找到活性更强的抗血小板聚集剂。方法以苯甲醚为原料,经3步反应制得中间体4-甲氧基-1,3-苯二甲酰氯,经与不同芳胺类化合物进行亲核取代反应制得目标化合物,用Born比浊法对制得的目标化合物进行体外抗血小板聚集活性的初筛。结果与结论共制得13个目标化合物,其结构经IR、1H-NMR和MS确证。其中9个化合物P2和P5~P12未见文献报道。以picotamide为阳性对照药物,对13个化合物进行了体外抗血小板聚集活性初筛,试验结果表明,化合物P8、P9和P12的抗血小板聚集活性很高,明显优于picotamide。     

Synthesis and beta-lactamase inhibitory activities of some clavulanic acid analogues

Clavulanic acid analogs lacking the C-3 carboxyl group are potent inhibitors of both plasmid and chromosomally mediated beta-lactamases. They exhibit only low intrinsic anti-bacterial activity, but potentiate the activity of ampicillin and cephaloridine against beta-lactamase producing Escherichia coli and Enterobacter cloacae in vitro. No synergism was observed in beta-lactamase negative strains. The E. coli TEM 1 and the E. cloacae P99 enzymes are inhibited in a progressive and irreversible manner by these compounds.     

Synthesis and biological activities of cyclic lanthionine enkephalin analogues: delta-opioid receptor selective ligands

The synthesis and biological test results of a series of enkephalin analogues incorporating the lanthionine modification are presented. The syntheses of four monosulfide-bridged analogues of enkephalins, Tyr-c[D-Ala(L)-Gly-Phe-D-Ala(L)]-OH (1a), Tyr-c[D-Val(L)-Gly-Phe-D-Ala(L)]-OH (1b), Tyr-c[D-Ala(L)-Gly-Phe-Ala(L)]-OH (1c), and Tyr-c[D-Val(L)-Gly-Phe-Ala(L)]-OH (1d), where Ala(L) and Val(L) denote the lanthionine amino acid ends linked by a monosulfide bridge to form the lanthionine structure, were successfully carried out via preparation of the linear peptide on solid support and cyclization in solution. In vitro binding assays against mu-, delta-, and kappa-opioid receptors and in vitro tests using GPI and MVD assays revealed that the dimethyl lanthionine analogues 1b and 1d, denoted as D-Val(L) in position 2, show substantial selectivity toward the delta-opioid receptor, while the unsubstituted analogues 1a and 1c, denoted as D-Ala(L) in position 2, bind to both mu- and delta-opioid receptors. The in vivo thermal escape assay by intrathecal administration showed that the analogues 1b and 1d are among the most potent ligands at producing antinociception through the delta-opioid receptor. The picomolar potencies of analogues 1a and 1c in the intrathecal (it.) assay strongly indicate that mu- and delta-opioid receptors interact synergistically to modulate the antinociceptive responses.     

Analgesic dipeptides. VI.: Synthesis and structure-activity relationships of N-terminal modified analogues of the analgesic compounds H-Xaa-Trp(Nps)-OMe (Xaa=Lys, Orn, Arg)

In order to determine the influence of the N-terminal amino group of the dipeptide derivatives H-Xaa-Trp(Nps)-OMe[Xaa = Lys (2a), Orn (2b), Arg (2c)] on their antinociceptive effects, the syntheses of their corresponding deaminated, acetylated and dimethylated analogues have been achieved. Deamino and dimethyl analogues of 2a,b,6a,b, and 18a,b were prepared by coupling the corresponding N omega-Z- and N omega-Z-N alpha-Me2 amino acids with H-Trp-OMe, using the DCC/HOSu method, followed by sulfenylation of the resulting compounds and removal of the Z groups. Guanidylation of 6b and 18b provided the arginine analogues 6c and 18c, respectively. Ac-Xaa-Trp(Nps)-OMe [Xaa = Lys (11a), Orn (11b) were synthesized by acetylation of H-Xaa(Z)-Trp(Nps)-OMe with acetic anhydride, in the presence of 4-dimethylaminopyridine, and subsequent removal of the Z groups. Coupling of Ac-Arg-OH.HC1 with H-Trp-OMe, using the DCC/HOSu procedure, followed by sulfenylation of the resulting 8:3 diastereomeric mixture of L,L and L,D dipeptides afforded Ac-ambo-Arg-Trp(Nps)-OMe 11c+11d. The antinociceptive effects of 6a-c, 11a-d, and 18 a-c were evaluated after i.c.v. administration in mice. The N alpha-acetyl dipeptides 11 were found to exhibit a naloxone-reversible antinociceptive effects comparable with those of 2, while N-deaminated and N,N-dimethylated analogues were inactive.     

Syntheses and structure-activity relationships of nonnatural beta-C-nucleoside 5'-triphosphates bearing an aromatic nucleobase with phenolic hydroxy groups: inhibitory activities against DNA polymerases

Five nonnatural beta-C-nucleoside 5'-triphosphates bearing a 3,4-dihydroxyphenyl (1TP), a 2-hydroxyphenyl (2TP), a 3-hydroxyphenyl (3TP), a 4-hydroxyphenyl (4TP), or a phenyl (5TP) group were synthesized, and their structure-activity relationships were examined for a series of DNA polymerase reactions in vitro under typical polymerase chain reaction conditions. We found that the 5'-triphosphates (1TP-5TP) are not incorporated into DNA strands but inhibit the DNA polymerase reactions in the presence of natural nucleoside 5'-triphosphates (dNTPs). 1TP having two phenolic hydroxy groups at the nucleobase moiety showed the most potent inhibitory effect against DNA synthesis by Ex Taq polymerase (IC(50) = 30 microM). The competition assay indicated that 1TP and dNTPs are most likely to affect DNA polymerase reactions competitively. This finding may raise the appealing possibility that artificial nucleoside 5'-triphosphates having phenolic hydroxy groups could exhibit potent inhibitory activity against DNA-directed enzymatic reactions.     

Synthesis of novel MKC-442 analogues with potent activities against HIV-1

Bis(alken-1-yloxy)methanes 2 were synthesized by reacting 2-cyclohexenol, 3-cyclohexenylmethanol, cinnamyl alcohol and its alpha-methyl analogue with dibromomethane. Condensation of 2 with 5, 6-disubstituted uracil derivatives 1 resulted in the desired MKC-442 analogues 3-6. The most active compounds, N-1 cinnamyloxymethyl- and N-1 2-methyl-3-phenylallyloxymethyl substituted 5-ethyl-6-(3, 5-dimethylbenzyl)uracils (5b and 6b), showed activity against wild-type HIV-1 in the nanomolar range, and against Y181C andY181C+K103N, mutant strains known to be resistant to MKC-442, in the micromolar range.     

Long lasting antinociceptive properties of enkephalin degrading enzyme (NEP and APN) inhibitor prodrugs

Prodrugs of phosphinic dual inhibitors of the enkephalin degrading enzymes, neutral endopeptidase (NEP) and aminopeptidase N (APN), corresponding to the formula H(3)N(+)CH(R(1))P(O)(OR)CH(2)CH(CH(2)Bip)CONHCH(CH(3))COOCH(2)Ph, with R(1) = CH(3) or Ph and R being a benzyl ester, a S-acyl-2-thioethyl derivative, or an acyloxyalkyl group, were synthesized to improve the poor central bioavailability of their precursors. As expected, these compounds (50 mg/kg, iv or ip) induced long lasting ( approximately 2 h) antinociceptive responses in the hot plate test in mice with a ceiling effect varying between 25 and 42% of analgesia. A very rapid hydrolysis of the carboxylate ester contrasting with a slow deprotection of the phosphinate group (t(1/2) approximately 1 h) was observed in serum while 80% of free drug was obtained after 1 h incubation with brain membranes. These results account for the long duration of action observed with these prodrugs.     

Analgesic dipeptide derivatives. 7. 3,7-Diamino-2-hydroxyheptanoic acid (DAHHA) containing dipeptide analogues of the analgesic compound H-Lys-Trp(Nps)-OMe.

A series of diastereomeric dipeptides, analogues of the analgesic compound H-Lys-Trp(Nps)-OMe (2), containing 3,7-diamino-2-hydroxyheptanoic acid (DAHHA) and 2-[(o-nitrophenyl)sulfenyl]tryptophan [Trp(Nps)] has been synthesized. These compounds were tested as enkephalin-degrading aminopeptidases (APs), AP-M and AP-B inhibitors, and analgesics. The inhibitory potencies and the antinociceptive effects depended on the stereochemistry of the compounds. (2S,3R)-DAHHA-L-Trp(Nps)-OMe (26d) was a highly potent and selective enkephalin-degrading APs inhibitor, with an IC50 value in the 10(-8) M range. Although this derivative was about 10(3)-fold more potent than 2 against these enzymes, their antinociceptive effects were completely similar. These results indicate that the inhibitory capacity of this series of Trp(Nps)-containing dipeptides against enkephalin-degrading enzymes is not an important factor for their antinociceptive effects.     

Synthesis and biological activities of 4-O-(difluoromethyl)-5-substituted-uracil nucleoside analogues

Various 4-O-difluoromethyl analogues of 5-substituted uridine (Urd), 2'-deoxyuridine (dUrd), and arabinofuranosyluracil (araU) nucleosides were prepared via a CF2-insertion reaction into 4-O-silylated nucleosides and evaluated for activity against herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) and cytotoxicity in human embryonic lung fibroblast (HELF) cell cultures. The introduction of the 4-substituent led to a strong reduction of antiviral activity for dUrd but not for araU analogues. Three of the 4,5-disubstituted uracil nucleoside derivatives, 4-O-(difluoromethyl)-5-bromo-araU (5c),-5-methyl-araU (5e), and -(E)-5-(2-bromovinyl)-araU (5g), displayed a high and selective inhibitory effect against HSV-1, but only 5e was effective against both HSV-1 and HSV-2 comparably with the antiherpes potential of the reference compounds 9-[(2-hydroxyethoxy)methyl]guanine (acyclovir) and 1-beta-D-arabino-furanosylthymine (araT).     

萘甲基三唑羧酸类化合物的合成及其抑制URAT1活性的研究

目的设计合成一类含萘甲基三唑结构的羧酸类化合物,并对其抑制尿酸转运体1(URAT1)的活性进行研究。方法以4-溴甲基萘、1H-1,2,4-三氮唑-3-硫醇和溴乙酸甲酯为起始原料,通过取代、水解等反应合成目标化合物,并对其抑制URAT1的活性进行研究。结果设计并合成了3个目标化合物,结构经1H-NMR和MS确证。活性测试结果显示化合物F-2和G-2具有比阳性对照药lesinurad还要强的URAT1抑制活性。结论设计了一条合成目标化合物的简易路线,该路线操作简便、路线短、收率高。目标化合物也具有一定的生物活性。     

Synthesis and iNOS inhibitory activities of thioflavones

A number of thioflavones has been synthesized and evaluated for their iNOS inhibitory activities. Thiowogonin (6) was obtained from naturally occurring chrysin in 5 steps. Other thioflavones were prepared from the corresponding flavones in a single step by the reaction with Lawesson's reagent. The biological activities of thioflavones were not enhanced by the functional group conversion from carbonyl to thiocarbonyl. Compounds 11 and 13 showed potent NO inhibitory activity at high concentration (40 uM), leading to the possible development of novel neuroprotective agents based on wogonin.     

N-(4-乙氧苯基)苯甲酰胺衍生物的合成与抗炎抗变态反应生物活性

目的以一类新药乙氧苯柳胺为先导化合物,合成取代苯甲酰苯胺衍生物并探讨其抗炎、抗变态反应生物活性。方法以取代苯甲酸为起始原料,通过氯化、缩合、电子等排、拼合和Mannich反应等制备目标化合物;用元素分析、IR1、H NMR光谱等方法确证目标化合物化学结构。结果设计并合成了10个目标化合物,其中7个化合物(LX001~LX005、LX008、LX010)尚未见文献报道;合成的目标化合物具有不同程度的抗炎、抗变态反应活性,其中LX002、LX004、LX010均具有较强的抗炎作用,LX002有较明显的抗变态反应活性。结论N(4乙氧苯基)苯甲酰胺衍生物具有较强抗炎作用和抗变态反应活性。     

吡咯烷类明胶酶抑制剂的合成及初步活性

目的设计合成一系列新型吡咯烷衍生物并测定其抑制明胶酶（MMP-2，MMP-9）的活性，研究其构效关系。方法以L-羟脯氨酸为原料。经多步反应合成吡咯烷类衍生物，采用体外抑酶试验测定化合物抑制明胶酶（MMP-2，MMP-9）的活性。结果合成了33个未见文献报道的吡咯烷衍生物，其结构经红外光谱、核磁共振氢谱及质谱确定。其中化合物A0、A8、A9、A10、B9、C10抑制明胶酶的活性较强。结论吡咯烷类衍生物对明胶酶有较强的抑制活性。有可能抑制肿瘤的发生、发展和转移，值得进一步研究。     

Synthesis and aldose reductase inhibitory activities of novel thienocinnolinone derivatives.

A novel series of tetrahydrothieno[2,3-h]cinnolinone derivatives were synthesized and evaluated in vitro for their ability to inhibit aldose reductase (ALR2), an enzyme involved in the appearance of diabetic complications. Compounds 2e and 2j exert a remarkable inhibitory effect, with IC(50) of 7.6 and 18 microM, respectively. These compounds incorporate a valid pharmacophore for aldose reductase inhibitory activity represented by a thienocinnolinone template linked through a pentamethylene spacer to a carboxylic function.     

Synthesis, opiate receptor affinity, and conformational parameters of [4-tryptophan]enkephalin analogues.

A series of analogues of the opioid peptide enkephalin with tryptophan substituted for phenylalanine in position 4 was synthesized by the solid-phase method. The [Trp4]enkephalin analogues and the corresponding [Phe4]enkephalin analogues displayed nearly parallel affinities in the opiate receptor binding assay throughout the series. In a conformational study fluorescence parameters were measured and intramolecular Tyr-Trp distances were estimated on the basis of resonance energy transfer experiments. No gross conformational differences were observed between analogues with widely differing opiate receptor affinity; however, small but significant changes in the intramolecular distance between the phenol ring and the indole moiety and/or in their relative orientation became apparent in some compounds. Identical intramolecular distances of 9.3 +/- 0.2 angstrom between the two aromatic rings were obtained with [Trp4,Met5]enkephalin, [Trp4,Leu5]enkephalin, and the N-terminal tetrapeptide comprised in the latter two analogues, indicating the existence of folded conformationas in 2 X 10(-5) M aqueous solution and demonstrating conformational analogy between these three peptides. The conformational parameters are discussed in relation to the observed affinities and the putative opiate receptor topography.     

Folate analogues. 21. Synthesis and antifolate and antitumor activities of N10-(cyanomethyl)-5,8-dideazafolic acid

A close analogue of the antileukemic agent 5,8-dideaza-N10 propargylfolic acid (2) was synthesized by replacing the propargyl moiety of 2 with a cyanomethyl group. This compound, N10-(cyanomethyl)-5,8-dideazafolic acid (3), was evaluated for its antifolate and antitumor activities in several biological test systems. Alkylation of diethyl N-(4-aminobenzoyl)-L-glutamate with bromoacetonitrile gave diethyl N-[4-[(cyanomethyl)amino]benzoyl]-L-glutamate (7). Reaction of 7 with 2 amino-6-(bromomethyl)-4-hydroxyquinazoline (9) in dimethylacetamide gave the corresponding diethyl ester 11, which was hydrolyzed to the target compound 3. The known antileukemic agent 2 was also synthesized for comparative studies by employing a modified procedure, which resulted in a better yield of this product. Both compounds 2 and 3 were evaluated for their antifolate activities by using two folate-requiring microorganisms, Streptococcus faecium and Lactobacillus casei. They were further evaluated as inhibitors of thymidylate synthase and dihydrofolate reductase derived from the above organisms, as well as for their antitumor activity by using selected tumor cells in culture. Compound 2 was found to be as equally potent as methotrexate (MTX) against S. faecium, and it was an excellent inhibitor of L. casei thymidylate synthase. The cyanomethyl analogue 3 was less active than 2 in all the test systems, except the inhibition of dihydrofolate reductase.     

Synthesis of phosphatidylinositol 3-kinase (PI3K) inhibitory analogues of the sponge meroterpenoid liphagal

Analogues of the sponge meroterpenoid liphagal have been synthesized and evaluated for inhibition of PI3Kα and PI3Kγ as part of a program aimed at developing new isoform-selective PI3K inhibitors. One of the analogues, compound 24, with IC?? values of 66 nM against PI3Kα and 1840 nM against PI3Kγ, representing a 27-fold preference for PI3Kα, exhibited enhanced chemical stability and modestly enhanced potency and selectivity compared with the natural product liphagal.