Heterocyclic derivatives.

摘要

This invention relates to heterocyclic derivatives which are histamine H-2 antagonists and which inhibit gastric acid secretion. According to the invention there is provided a guanidine derivative of the formula I:
<Chemistry id="chema01" num="0001"><Image id="ia01" he="24" wi="84" file="IMGA0001.TIF" imgContent="chem" imgFormat="TIFF" inline="no" /></Chemistry>

in which R<Sup>1</Sup> and R<Sup>2</Sup>, same or different, are hydrogen or 1-10C alkyl, 3-8C cycloalkyl, 4-14C cycloalkylalkyl, each alkyl, cycloalkyl or cycloalkylalkyl optionally carrying one or more F, Cl or Br atoms, provided that one of R<Sup>1</Sup> and R<Sup>2</Sup> is halogen-substituted, or R<Sup>2</Sup> is hydrogen and R<Sup>1</Sup> is R<Sup>S-</Sup>E-W- in which W is 2-6 alkylene optionally substituted by 1 or 2 1-4C alkyls, E is O,S,SO, SO<Sub>2</Sub> or NR<Sup>6</Sup> in which R<Sup>6</Sup> is H or 1-6C alkyl, R<Sup>5</Sup> is H or 1-6C alkyl optionally substituted by 1 or 2 1-4C alkyls, or R<Sup>5</Sup> and R<Sup>6</Sup> are joined to form a pyrrolidine, piperidine, morpholine, piperazine or N-methylpiperazine ring; ring X is a heterocyclic ring; A is phenylene or 5-7C cycloalkylene, or a 1-8C alkylene into which is optionally inserted one or two groups; and R<Sup>3</Sup> and R<Sup>4</Sup> are a variety of radicals and the pharmaceutically-acceptable acid-addition salts thereof. Manufacturing processes and pharmaceutical compositions are also described.