Three new EPR spectra ($\mathrm{Si}\ensuremath{-}A14,\ensuremath{-}A15, \mathrm{and} \ensuremath{-}A16$) and two previously known spectra ($\mathrm{S}\mathrm{i}\ensuremath{-}P2 \mathrm{and} \ensuremath{-}P4$) are observed for the first time in electron-irradiated silicon. The microscopic defect models are established as multivacancy-oxygen complexes with the oxygen(s) in Si-O-Si structure inside the 110g vacancy chain: a (divacancy plus oxygen) for $\mathrm{S}\mathrm{i}\ensuremath{-}A14$, a (divacancy plus two oxygen) for $\mathrm{S}\mathrm{i}\ensuremath{-}P2$, a (trivacancy plus oxygen) for $\mathrm{S}\mathrm{i}\ensuremath{-}P4$, a (trivacancy plus two oxygen) for $\mathrm{S}\mathrm{i}\ensuremath{-}P5$, and a (trivacancy plus three oxygen) for $\mathrm{S}\mathrm{i}\ensuremath{-}A15$. The number of vacancies in the 110g chain is determined from the zero-field fine structure and the number of oxygens from the evolutionary kinetics, with the $g$ tensor, $^{29}\mathrm{Si}$ hyperfine structure, and stress response providing strong supportive evidence. It is emphasized that some of these oxygen-dependent defects play an important role as trapping centers for other point defects.