Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
inter-strŭo, struxi, structum, 3, v. a., to join together; to add (poet. and eccl. Lat.): qua spina interstruit artus, Sil. 10, 147: nullam distinctionem, Tert. adv. Marc. 4, 39 med.