Hexylsilane-mediated direct amidation of amino acids with a catalytic amount of 1,2,4-triazole

In this study, we report amino acid amidation using hexylsilane and a catalytic amount of 1,2,4-triazole. The conventional protection/deprotection method for the α-amino group of amino acids is not required. The corresponding α-amino amides were obtained in moderate to good yields with low to no racemization.

In Vitro and in Vivo Study of a Photostable Quinone Compound with Enhanced Therapeutic Efficacy against Chagas Disease

Chagas disease, a neglected tropical disease caused by the protozoan Trypanosoma cruzi poses a significant health challenge in rural areas of Latin America. The current pharmacological options exhibit notable side effects, demand prolonged administration, and display limited efficacy. Consequently, there is an urgent need to develop drugs that are safe and clinically effective. Previously, we identified a quinone compound (designated as compound 2) with potent antiprotozoal activity, based on the chemical structure of komaroviquinone, a natural product renowned for its antitrypanosomal effects. However, compound 2 was demonstrated considerably unstable to light. In this study, we elucidated the structure of the light-induced degradation products of compound 2 and probed the correlation between the quinone ring's substituents and its susceptibility to light. Our findings led to the discovery of quinones with significantly enhanced light stability, some of which exhibiting antitrypanosomal activity. The most promising compound was evaluated for drug efficacy in a mouse model of Chagas disease, revealing where a notable reduction in blood parasitemia.

Synthesis and Evaluation of Quinone Derivatives for Activity against Trypanosome cruzi

A series of quinone derivatives with a variety of side chains were synthesized. These synthetic quinone compounds were evaluated for in vitro antitrypanosomal activity against trypomastigotes and amastigotes of Trypanosoma cruzi, the causative agent of Chagas disease. Measurement of solubility of quinones and their ability to permeate cell membranes were assessed to address their possible use as oral drugs. Some synthesized compounds exhibited potent antitrypanosomal activity. However, most compounds with a promising activity showed poor solubility that did not seem suitable for oral usage. Meanwhile, compound 5a, an N-tert-butoxycarbonylpiperidine derivative, exhibited good antitrypanosomal activity, ability to permeate membranes, and good solubility.

Catalyst-controlled site-selective asymmetric epoxidation of nerylamine and geranylamine derivatives

Novel catalysts for site- and enantioselective epoxidation of nerylamine and geranylamine derivatives have been developed. Although mCPBA oxidation took place selectively at the more electron-rich double bond to give the 6,7-epoxides, these catalysts provide the 2,3-epoxides in moderate to high enantioselectivity via the oxidation of the relatively electron-deficient double bond.

Aerobic photooxidative synthesis of 2-aryl-4-quinazolinones from aromatic aldehydes and aminobenzamide using catalytic amounts of molecular iodine

This study reports a safe, mild, and environmentally benign synthetic method toward 2-aryl-4-quinazolinones through a cyclization–oxidation sequence using a catalytic amount of iodine, harmless visible light irradiation, and molecular oxygen.

Continuous and convergent access to vicinyl amino alcohols

A four module convergent chemical assembly system delivers two classes of vicinyl amino alcohol and five APIs.

Aerobic photooxidative direct asymmetric aldol reactions of benzyl alcohols using water as the solvent

We report an aerobic photooxidative direct asymmetric aldol reaction using water as the solvent.

Molecular-iodine-catalyzed aerobic oxidative synthesis of β-hydroxy sulfones from alkenes

The synthesis of β-hydroxy sulfones from alkenes and sodium sulfinates under aerobic oxidative conditions was achieved in the presence of a catalytic amount of molecular iodine.

[Evaluation of a method to determine the myocardial uptake from 123I-BMIPP myocardial SPECT and its significance]

We examined methods of calculating myocardial uptake (TU) of 123I-BMIPP by SPECT, and compared TU to heart function (ejection fraction (EF), cardiac output (CO), cardiac index (CI)) calculated by left ventriculography. Forty-two patients with acute myocardial infarction were classified into 5 groups; within 1 week (I), from 1 to 2 weeks (II), from 2 weeks to 1.5 months (III), from 1.5 to 3 months (IV) and more than 3 months (V) after percutaneous transluminal coronary angioplasty (PTCA). Chest depth (Tw) was calculated by measuring the thoracic absorption rate of 123I. In calculating TU, the myocardial count was calculated from short-axis tomograms, and then absorption was corrected using Tw to calculate each value on early-phase image (E) and delay-phase image (D). The influence of lung uptake on myocardial count was only 1.76%. When TU was compared to heart function, there were correlations between group I and group V. Especially in group V D-TU was a significantly correlated with heart function. In heart function CI, but not EF nor CO, was significantly correlated with TU. It was suggested that the correlation between TU and heart function reflected the infarct condition before PTCA in group I, and that the individual difference in recovery of fatty acid metabolism in group V. The significant correlation between D-TU and CI suggests that D-TU reflects heart function and fatty acid metabolism, although TU is influenced by differences in physical status.

[Strategy for the treatment of hepatocellular carcinoma]

Hepatocellular carcinoma is a refractory cancer for the following two reasons: the tumor characteristics, including formation of tumor thrombus in the portal vein, metastasis within the liver and multicentricity of growth; and liver function disturbance due to cirrhotic change by B- or C-type viral infection. The most desirable treatment is hepatic resection, the only method producing a disease-free condition. However, there are not many cases that meet the indications for hepatic resection, since they have advanced lesions and/or liver dysfunction. If one cannot perform a hepatic resection, other suitable therapies should be selected, including transcatheter arterial embolization, percutaneous ethanol injection therapy, ligation of hepatic artery, irradiation, chemotherapy from hepatic artery via reservoir and so on. Combined therapy may sometimes be necessary for satisfactory efficacy. For long-term survival it is very important to do a close follow-up study over a long period. This encourages us to detect new lesions earlier and then perform suitable therapy again. Notifying patients of the disease and obtaining informed consent are needed for this long-term follow-up and treatment. When patients were examined who had first undergone hepatic resection and then hepatic re-resection for recurrence, we found that their survival rate was not different from that in the non-recurrent cases. This result indicates that overcoming refractory hepatocellular carcinoma requires a multidisciplinary treatment in which hepatic resection is the main means.

[The relation between ECG findings and lesions of acute and old myocardial infarction in autopsy cases]

Sixty-four elderly autopsy cases with acute myocardial infarction (AMI) were investigated in Nagoya Koseiin Geriatric Hospital. First AMI was observed in 35 cases, and recurrent AMI in 29. The primary causes of death were cardiac rupture and congestive heart failure in the first AMI and the recurrent AMI, respectively. The most frequent ECG findings before AMI were ischemic ST-T-change (57%) and Q-QS abnormality (41%) on the first and recurrent AMI, respectively. The ECG findings were normal in 6 (21%) of 29 recurrent MI cases. There was a tendency towards Q-QS abnormality in large size old MI, but not in small size MI. In 29 cases with recurrent AMI, the positional relationship between the old MI and the AMI was classified into 3 groups of different area, same area, and different and same area according to the Maccarie classification. The frequency in our cases was similar in the 3 groups. Ten cases with different area were further classified into 3 groups, i.e. opposite, adjacent, and opposite and adjacent. Opposite cases consisted of 4 (40%) cases, while opposite and adjacent consisted of 6 (60%). It is suggested that the recurrent AMI is more likely to be fatal when AMI occurs opposite to a previous lesion rather than adjacent to an old lesion.