We describe the products of the reaction of the hydroperoxy radical (HO2) with the alkylperoxy radical formed following addition of the nitrate radical (NO3) and O-2 to isoprene. NO3 adds preferentially to the C-1 position of isoprene (>6 times more favorably than addition to C-4), followed by the addition of O-2 to produce a suite of nitrooxy alkylperoxy radicals (RO2). At an RO2 lifetime of similar to 30 s, delta-nitrooxy and beta-nitrooxy alkylperoxy radicals are present in similar amounts. Gas-phase product yields from the RO2 + HO2 pathway are identified as 0.75-0.78 isoprene nitrooxy hydroperoxide (INP), 0.22 methyl vinyl ketone (MVK) + formaldehyde (CH2O) + hydroxyl radical (OH) + nitrogen dioxide (NO2), and 0-0.03 methacrolein (MACR) + CH2O + OH + NO2. We further examined the photochemistry of INP and identified propanone nitrate (PROPNN) and isoprene nitrooxy hydroxyepoxide (INHE) as the main products. INHE undergoes similar heterogeneous chemistry as isoprene dihydroxy epoxide (IEPOX), likely contributing to atmospheric secondary organic aerosol formation.