Inotropic agent

Friedel-Crafts acylation of 3,3-dimethyl-2-indolinone by succinic anhydride gives 3,3-dimethyl-5-(3-catboxyptopionyl)-2-indoline, which is used as an intermediate in the preparation of inotropic agents for treatment of heart failure (94). Antibacterial phlotophenone derivatives have been prepared by Friedel-Crafts acylation with ptopanoyl chlotide (95). 

Artificial Hearts. Congestive heart failure (CHF) is a common cause of disabiHty and death. It is estimated that three to four million Americans suffer from this condition. Medical therapy in the form of inotropic agents, diuretics (qv), and vasofilators is commonly used to treat this disorder (see Cardiovascularagents). Cardiac transplantation has become the treatment of choice for medically intractable CHF. Although the results of heart transplantation are impressive, the number of patients who might benefit far exceeds the number of potential donors. Long-term circulatory support systems may become an alternative to transplantation (5). 

Pyridyl-4-bromo-6-oxo-5,6,7,8-tetrahydrothiazolo[5,4-g]quinolones and analogues were prepared and tested as potential inotropic agents for treatment of heart failure. For example, the 2-(4-pyridyl) substituted thiazoloquinolone 38 gave a 122% increase in contractility of guinea pig papillary muscle (89EUP1). 

Synthesis, pharmacology, and molecular modeling of 2-pyridone derivatives as inotropic agents 97F331. 

Treatment focuses on increasing CO with positive inotropic agents and/or replacing intravascular fluids... 

Treatment involves a delicate balance between diuretics, vasodilators, and inotropic agents... 

Dobutamine is a P-adrenergic inotropic agent that can be utilized for improvement of cardiac output and oxygen delivery. Doses of 2 to 20 mcg/kg per minute increase cardiac index however, heart rate increases significantly. Dobutamine should be considered in septic patients with adequate filling... 

Dobutamine (76), on the other hand, is a dopamine derivative which does not act centrally, but is of interest because of its coronary vasodilator properties. Such drugs are potentially of value in treatment of angina pectoralis. Further, it is now undergoing extensive clinical trials as an inotropic agent for use in heart failure. Its synthesis is effected by Raney nickel catalyzed reduction of methyl p-methoxyvinylphenylketone (75) to its dihydro analog followed by reductive alkylation with p-(3,4-dimethoxyphenyl)ethylamine. The ether groups are cleaved with HBr to complete the synthesis of... 

IV vasodilators and inotropic agents are generally used in conjunction with the IABP to maximize hemodynamic and clinical benefits. 

Inotropic agents and vasopressors are generally not indicated in the initial treatment of hypovolemic shock (assuming that fluid therapy is adequate),... 

Tertiary benzamides whose N-atom is part of a cyclic system can also be hydrolyzed metabolically as shown in the following examples. The hydrolysis of the amide group in 6-[4-(3,4-dimethoxybenzoyl)piperazin-l-yl]-3,4-di-hydro-1 //-quinolin-2-one (OPC-8212, 4.85), an inotropic agent, occurred in rats, mice, dogs, monkeys, and humans [54], After oral administration to rats, both products of hydrolysis, namely 3,4-dimethoxybenzoic acid (veratric acid, 4.86) and piperazine-l//-quinolin-2-one (4.87) were detected in the plasma, urine, and feces. 

Just as Class III agents can exhibit positive inotropy, some positive inotropic agents demonstrate Class III electrophysiologic activity. The increase in intracellular calcium-ion concentration produced by the inotropic... 

In the United States, two potent orally active positive inotropic agents, CI-914 [imazodan hydrochloride CAS 89198-09-4, (15)] and CI-930 [CAS 86798-59-6, (16)], both characterized by a 4T(l/7-imidazol-l-yl)phenyl substituent attached to C-6 of a 4,5-dihydro-3(2//)-pyridazinone system, have been developed [16]. Patents exist on compounds of this type and related unsaturated pyridazinones [17-21] and also on homologues in which the... 

Another pyridazinone-derived inotropic agent with cAMP phosphodiesterase inhibitory activity is pimobendan [UD-CG-115-BS CAS 74150-27-9, (21)], which has been developed in Germany. In contrast to the imidazolyl-phenylpyridazinone CI-930 (16) discussed above, in pimobendan the imidazole nucleus (substituted at C-2 by a 4-methoxyphenyl group) is fused to the benzene moiety attached to C-6 of the 4,5-dihydro-5-methyl-3(2//)-pyri-dazinone system. 

In the United States, compound RGW-2938 (47) has been developed as a selective positive inotropic agent its synthesis and pharmacological actions have been reviewed [161]. Related compounds, in which the dihydro-pyridazinone system is replaced by a benzoxazinyl system instead of the quinazoline system, have recently been studied in India and in the United States [162,163]. From this series, bemoradan (48) was found to be a very potent orally active, long-acting inotropic vasodilator agent in canine models (i.v. ED5o = 5.4 //g/kg 24h duration of action) [163]. 

H. G. Ramjit, M. M. Singh and A. B. Coddington, Gas chromatographic/mass spectro-metric analysis of methyl methanesulfonate and ethyl methanesulfonate in the bismesy-late salt of DPI 201-106, a positive inotropic agent for the treatment of heart failure. Journal of Mass Spectrometry, 31(8), 867-872.1996. 

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