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We have surveyed molecular lines, including N2H+, CCS, HC3N, CH3OH, SiO, C34S, SO, OCS, H13CO+, HN13C, C34S, and CCH, toward massive clumps associated with infrared dark clouds (IRDCs) by using the Nobeyama Radio Observatory 45 m telescope and the Atacama Submillimeter Telescope Experiment 10 m telescope. The [CCS]/[N2H+] ratios are found to be mostly lower than unity. This suggests that most of massive clumps are chemically more evolved than low-mass starless cores. We have detected the CH3OH J=7-6 lines (338 GHz) toward 18 objects, and found that the CH3OH lines tend to have broader linewidth in the MSX dark objects than in the others, the former being younger or less luminous than the latter. The broad emission seems to originate from the interaction between an outflow and an ambient cloud. Thus, this may suggest that outflow interaction plays an important role in production of the gas phase CH3OH in the early stage of high-mass star formation. We discuss the evolutionary stages of the massive clumps associated with IRDCs, by comparing their chemical compositions with those of high-mass protostellar objects, low-mass cores, and shocked regions.
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