@Test
public void testBug2276507() {

    IMolecularFormula mf1 = new MolecularFormula();
    mf1.addIsotope(builder.newInstance(IIsotope.class, "C"), 1);
    mf1.addIsotope(builder.newInstance(IIsotope.class, "H"), 4);
    Assert.assertEquals("CH4", MolecularFormulaManipulator.getString(mf1));
}