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A novel class of nonantioxidant dual inhibitors of both CO and 5-LO is described. The balance between the activity against CO and 5-LO can be shifted by modifying the substitution pattern of the phenyl moiety at the 6-position of the pyrrolizine ring. Structure-activity relationships are discussed. Compound 3e with a 4-Cl substituent (IC50 = 0.21 microM (CO); 0.18 microM (5-LO)) and 3n with a 4-OCH3 substituent (IC50 = 0.1 microM (CO); 0.24 microM (5-LO)) are the most potent and well-balanced dual inhibitors of both enzymes. The inhibition of CO was determined in a bovine thrombocyte intact cell assay and that of 5-LO using intact bovine PMNL. Compound 3e was also investigated in human cells.

Vanillin, a food flavoring agent, has been shown to suppress cancer cell migration and metastasis in a mouse model, but its mechanism of action is unknown. In this report, we have examined the antimetastatic potential of vanillin and its structurally related compounds, vanillic acid, vanillyl alcohol, and apocynin on hepatocyte growth factor (HGF)-induced migration of human lung cancer cells by the Transwell assay. Vanillin and apocynin could inhibit cell migration, and both compounds selectively inhibited Akt phosphorylation of HGF signaling, without affecting phosphorylation of Met and Erk. Vanillin and apocynin could inhibit the enzymatic activity of phosphoinositide 3-kinase (PI3K), as revealed by an in vitro lipid kinase assay, suggesting that inhibition of PI3K activity was a mechanism underlying the inhibitory effect on cancer cell migration, and the presence of an aldehyde or ketone group in the vanillin structure was important for this inhibition. Vanillin and apocynin also inhibited angiogenesis, determined by the chick chorioallantoic membrane assay.

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The new analogue 2 of combretastatin A-4 was discovered to be an inhibitor of tubulin polymerization with an IC50 of 7.6 microM and reduced angiogenesis in the in vivo chick embryo model. Interestingly, in a series of 2,3-diarylmaleimides closely related to this lead, no other compound was found to be active in the tubulin polymerization assay. However, by screening in the in vivo chick embryo assay 10 was identified as a potent angiogenesis inhibitor indicating an alternative target. Indeed, molecular modeling studies suggest a reasonable binding mode of 10 at the ATP-binding site of the model kinase CDK2. Motivated by these results, analogues of 10 were screened for inhibitory activity in a panel of 12 selected protein kinases and a high affinity of 10 to VEGF-R2 was found showing an IC50 of 2.5 nM. Structure-activity relationships (SAR) for this compound series with the isolated enzyme and equivalent antiangiogenic activity in the chick embryo assay are presented herein.

The identification and characterisation of the isoenzyme cyclooxygenase 2 (COX-2) stimulated investigations to develop efficient non-steroidal anti-inflammatory drugs with reduced side effects compared to standard NSAIDs. This review will focus on the structural features needed to achieve COX-2 selectivity. Five structural classes can be identified together with a class bearing little or no resemblance to one another in their molecular structure. The most interesting point is the very distinct structure/activity relationship. On the one hand only minor modifications to a particular compound induce a drastic change in its COX selectivity and on the other hand the structural prerequisites in terms of molecular shape, lipophilicity, electron density, flexibility, polarity and H-bonding dynamics allow a wide range of diversity.

The indolo[2,1- b]quinazoline alkaloid tryptanthrin has previously been identified as the cyclooxygenase-2 (COX-2) inhibitory principle in the extract ZE550 prepared from the medicinal plant Isatis tinctoria (Brassicaceae). We here investigated the potential inhibitory activity of tryptanthrin and ZE550 on COX-2, COX-1 in cellular and cell-free systems. A certain degree of selectivity towards COX-2 was observed when COX-1-dependent formation of thromboxane B(2) (TxB(2)) in HEL cells and COX-2-dependent formation of 6-ketoprostaglandin F(1alpha) (6-keto-PGF(1alpha)) in Mono Mac 6 and RAW 264.7 cells were compared. Preferential inhibition of COX-2 by two orders of magnitude was found in phorbol myristate acetate (PMA) activated bovine aortic coronary endothelial cells (BAECs). Assays with purified COX isoenzymes from sheep confirmed the high selectivity towards COX-2. The leukotriene B(4) (LTB(4)) release from calcium ionophore-stimulated human granulocytes (neutrophils) was used as a model to determine 5-lipoxygenase (5-LOX) activity. Tryptanthrin and the extract ZE550 inhibited LTB(4) release in a dose dependent manner and with a potency comparable to that of the clinically used 5-LOX inhibitor zileuton.

Antiepileptic drugs (AEDs) cover a broad spectrum of pathological conditions ranging from seizures following congenital or acquired brain disorders to behavioural and psychiatric disorders and recently neuropathic pain. The need for novel antiepileptics raises from the expanding field of indications as well as from the fact, that special seizure types are refractory to common AEDs. In addition, many of the conventional antiepileptic drugs exhibit an unfavourable side-effect profile. Since there is growing evidence, that NMDA receptor activation might play a crucial role in epilepsy, NMDA receptor antagonists have become compounds of interest in preventing and treating seizures. This review focuses on NMDA receptor antagonistic compounds, which are already in use for the treatment of epileptic seizures (i. e. MgSO4, felbamate) and compounds in clinical trials (i. e. remacemide, ADCI). Further interest is put on NMDA antagonists in preclinical and biological testing (memantine, dizocilpine, conantokins, Co101244/PD174494, ifenprodil, arcaine, L-701,324, eliprodil, CGP40116, LY235959, LY233053, MRZ2/576, LU73068, 4-Cl-KYN). Some of the latter compounds are predominantely of academic interest (i. e. 4-Cl-KYN), others (i. e. dizocilpine, LY235959, LY233053) might be of therapeutical value when combined with conventional AEDs. In order to reduce adverse effects in antiepileptic medication using NMDA antagonists, special interest will be focused on subtype selective compounds. In this respect, Co101244, a novel potent and selective NR1/2B NMDA receptor antagonist might be a lead for therapeutically promising compounds.