Thiazolidin-4-one formation. Mechanistic and synthetic aspects of the reaction of imines and mercaptoacetic acid under microwave and conventional heating

Microwave irradiation of a mixture of benzylidene-anilines and mercaptoacetic acid in benzene gives 1,3-thiazolidin-4- ones in very high yield (65–90%), whereas the same reaction performed through using the conventional method, at refluxtemperature, requires a much longer time and gives a much lower yield (25–69%). This difference seems to be due to someintermediates and by-products formed during the conventional reaction. On the basis of 1H NMR studies, two differentmechanisms, acting in benzene and in DMF, respectively, have been hypothesized for the thiazolidin-4-one system formation

Antitumor Agents 6. Synthesis, Structure-Activity Relationships, and Biological Evaluation of Spiro[imidazolidine-4,3′-thieno[2,3-g]quinoline]-tetraones and Spiro[thieno[2,3-g]quinoline-3,5′- [1,2,4]triazinane]-tetraones with Potent Antiproliferative Activity†

Two series of quinolinquinone derivatives, 2′H-spiro[imidazolidine-4,3′-thieno[2,3-g]quinoline]-2,4′,5,9′- tetraones (2a-n) and 2H-spiro[thieno[2,3-g]quinoline-3,5′-[1,2,4]triazinane]-3′,4,6′,9-tetraones (3a-e), were designed and synthesized using the previously described ethyl 3-amino-4,9-dioxo-2,3,4,9-tetrahydrothieno[2,3- g]quinoline-3-carboxylate (1) as a starting material. All compounds were evaluated for their antiproliferative activity against a panel of representative liquid and solid human tumor cell lines and exhibit IC50 values in the micromolar/submicromolar range. Series 2 displayed higher cytotoxicity than did series 3. The nature of the substituents on both imidazoline and triazinane N1 nitrogen markedly affected the activity profile of these series. Spectrophotometric and fluorescence measurements as well as unwinding assays performed on the most cytotoxic compounds, 2c, 2g, and 2k, showed that they are nonintercalative DNA agents and inhibit the catalytic activity of Topo II in a concentration-dependent mode. 2g was the most active Topo II inhibitor with activity levels comparable to those of VP-16

Antitumor Agents. 5. Synthesis, Structure-Activity Relationships, and Biological Evaluation of Dimethyl-5H-pyridophenoxazin-5-ones, Tetrahydro-5H-benzopyridophenoxazin-5-ones, and 5H-Benzopyridophenoxazin-5-ones with Potent Antiproliferative Activity

New antiproliferative compounds, dimethyl-5H-pyrido[3,2-a]phenoxazin-5-ones (1-6), tetrahydro-5Hbenzopyrido[ 2,3-j]phenoxazin-5-ones (7-9), and 5H-benzopyrido[3,2-a]phenoxazin-5-ones (10-12) were synthesized and evaluated against representative human neoplastic cell lines. Dimethyl derivatives 1-6 were more active against carcinoma than leukemia cell lines. The tetrahydrobenzo derivatives 7-9 were scarcely active, whereas the corresponding benzo derivatives 10-12 showed notable cytotoxicity against a majority of the tested cell lines. Molecular modeling studies indicated that the high potency of 10 and 11, the most cytotoxic compounds of the whole series, could be due to the position of the condensed benzene ring, which favors ð-ð stacking interactions with purine and pyrimidine bases in the DNA active site. Biological studies suggested that 10-12 have no effect on human topoisomerases I and II and that they induce arrest at the G2/M phase

Antitumor Agents. 2. Synthesis, Structure-Activity Relationships, and Biological Evaluation of Substituted 5H-Pyridophenoxazin-5-ones with Potent Antiproliferative Activity

New antiproliferative compounds, 5H-pyrido[3,2-a]phenoxazin-5-ones (1-10), 5H-benzophenoxazin- 5-one (11), 5H-pyrido[2,3-a]phenoxazin-5-one (12), 5H-pyrido[3,4-a]phenoxazin-5-one (13), and 5H-pyrido[4,3-a]phenoxazin-5-one (14), were synthesized and evaluated against representative human neoplastic cell lines. The excellent cytotoxic activity of these polycyclic phenoxazinones, structurally related to the actinomycin chromophore, is discussed in terms of structural changes made to rings A and D (Chart 1). Electron-withdrawing or electron-donating substituents were introduced at different positions of ring A to probe the electronic and positional effects of the substitution. A nitro group in R2 or in R1 increases the cytotoxic activity, whereas electron-donating methyl groups in any position lead to 10- to 100-fold decreasing of the activity. The low antiproliferative activity of benzophenoxazinone 11 and pyridophenoxazinones 13 and 14 confirms the crucial role of pyridine nitrogen in the W position of ring D in DNA binding. The unexpected high activity exhibited by 12, which has the nitrogen in the X position, could be ascribed to a different mechanism of action, which needs further investigation

Antitumor Agents. 1. Synthesis, Biological Evaluation, and Molecular Modeling of 5H-Pyrido[3,2-a]phenoxazin-5-one, a Compound with Potent Antiproliferative Activity

The iminoquinone is an important moiety of a large number of antineoplastic drugs and plays a significant role in the nucleus of actinomycins, powerful, highly toxic, natural antibiotics that target DNA as intercalating agents. A series of polycyclic iminoquinonic compounds, 2-amino-3H-phenoxazin-3-one (1), 2-amino-1,9-diacetyl-3H-phenoxazin-3-one (2), 2-acetylamino- 3H-phenoxazin-3-one (3), 3H-phenoxazin-3-one (4), 5H-pyrido[3,2-a]phenoxazin-5-one (5), and 5H-pyrido[3,2-a]phenothiazin-5-one (6), strictly related to the actinomycin chromophore, were synthesized for developing new anticancer intercalating drugs. The antiproliferative activity of these compounds, evaluated against representative human liquid and solid neoplastic cell lines, showed that 5 and its isoster 6 were the most active compounds inhibiting cell proliferation in a submicromolar range. Compound 5 was also evaluated against KB subclones (KBMDR, KB7D, and KBV20C), which overexpress the MDR1/P-glycoprotein drug efflux pump responsible for drug resistance. All the above KB subclones did not show altered sensitivity to the antiproliferative activity of 5. UV-vis and 1H NMR spectroscopy experiments support the phenoxazinone 5/DNA binding. Molecular mechanics methods were used to build a three-dimensional model of the 5/[d(GAAGCTTC)]2 complex. Electrostatic interactions between the hydrogen of the positively charged pyridine nitrogen of 5 and the negatively charged oxygen atoms (O4¢ and O5¢) of the cytosine C5 residue together with stacking forces contribute to the high antiproliferative activity. The metal(II)-assisted synthesis procedure of 5 is described, and the formation mechanism is proposed

Multiprofessional and intrahospital experience for diagnosis and treatment of pulmonary arterial hypertension.

Background. Referral centres for pulmonary hypertension will provide care by a multiprofessional team, which should as a minimum comprise: consultant physicians with a special interest in PH, clinical nurse specialist, radiologist, cardiologist with expertise in echocardiography. Aims. this study sought to determine whether the experience of the establishment of a clinic for pulmonary arterial hypertension, initially created only for the treatment and diagnosis of heart failure, may be considered positive. Methods. From 1 July 2008 to January 1, 2012 we evaluated 80 patients in our ambulatory dedicated to the diagnosis and treatment of PAH. All patients were performed to clinical evaluation, ECG, and echocardiography with estimation of the sPAP. Then we evaluated the functional capacity through cardiopulmonary exercise testing or six minute walking test (6MWT). RHC was required to confirm the diagnosis of pulmonary arterial hypertension. Results. 80 patients (mean age: 50.9 ± 18.68 years, 31 males) were evaluated in our center; the largest groups subjected to screening were thalassemia (21 subjects), rheumatologic patients (18 patients), respirators, suspected of "outof Proportion" (12 patients) and 4 patients with OSAS. 8 adult congenital heart patients. A diagnosis of PAH after right heart catheterization was possible in 25 cases. In particular, among patients with pulmonary arterial hypertension, 8 had a rheumatic etiology (systemic sclerosis), 2 postthromboembolic disease, 5 patients had congenital heart disease, 1 patient with HIV infection, 1 patient with thalassemia major, 1 chronic lymphocytic leukemia and 1 with myelodysplasia. Conclusions. The initial experience of our center and network within our hospital may be considered positive, because it permitted to patients easy access to hospital services, to undertake a comprehensive prognostic stratification and to recognize the early signs of worsening in subsequent tests

Multiprofessional and Intrahospital Experience for Diagnosis and Treatment of Pulmonary Arterial Hypertension

Background. Referral centres for pulmonary hypertension will provide care by a multiprofessional team, which should as a minimum comprise: consultant physicians with a special interest in PH, clinical nurse specialist, radiologist, cardiologist with expertise in echocardiography. Aims. this study sought to determine whether the experience of the establishment of a clinic for pulmonary arterial hypertension, initially created only for the treatment and diagnosis of heart failure, may be considered positive. Methods. From 1 July 2008 to January 1, 2012 we evaluated 80 patients in our ambulatory dedicated to the diagnosis and treatment of PAH. All patients were performed to clinical evaluation, ECG, and echocardiography with estimation of the sPAP. Then we evaluated the functional capacity through cardiopulmonary exercise testing or six minute walking test (6MWT). RHC was required to confirm the diagnosis of pulmonary arterial hypertension. Results. 80 patients (mean age: 50.9 ± 18.68 years, 31 males) were evaluated in our center; the largest groups subjected to screening were thalassemia (21 subjects), rheumatologic patients (18 patients), respirators, suspected of “outof Proportion” (12 patients) and 4 patients with OSAS. 8 adult congenital heart patients. A diagnosis of PAH after right heart catheterization was possible in 25 cases. In particular, among patients with pulmonary arterial hypertension, 8 had a rheumatic etiology (systemic sclerosis), 2 postthromboembolic disease, 5 patients had congenital heart disease, 1 patient with HIV infection, 1 patient with thalassemia major, 1 chronic lymphocytic leukemia and 1 with myelodysplasia. Conclusions. The initial experience of our center and network within our hospital may be considered positive, because it permitted to patients easy access to hospital services, to undertake a comprehensive prognostic stratification and to recognize the early signs of worsening in subsequent tests

Non-cardiovascular comorbidities in heart failure patients and their impact on prognosis

With the aging of the population and improvement of life expectancy of patients with heart disease, there is an increase in non-cardiovascular (CV) comorbidities affecting chronic heart failure (HF) patients. The increased prevalence of different CV and non-CV comorbidities is a rising problem in the management of patients with HF, mostly because these comorbidities may lead to poor prognosis, increase of hospitalizations and mortality rate. Recently, important data from multicenter randomized studies point to diabetes mellitus or iron deficiency as new pharmacological targets, and this highlights the need of broad expertise for the 21st-century cardiologist. The management of HF should take into account non-CV comorbidities. In this review, we discuss novel aspects of non-CV comorbidities in HF patients and emphasize the impact on prognosis