Block polymers are a class of versatile self-assembling soft materials that can form exquisite nanostructures for applications including ion transport membranes for batteries and fuel cells, and templates for inorganic oxide catalysts. Using molecular dynamics simulations and transferable force fields, we designed a series of symmetric triblock amphiphiles (or high-χ “block oligomers”) comprising incompatible sugar-based (A) and hydrocarbon (B) blocks that can self-assemble into ordered nanostructures with full domain pitches as small as 1.2 nm. Depending on the chain length and block sequence, the ordered morphologies include lamellae (LAM), perforated lamellae, and hexagonally-perforated lamellae (HPL). Above the order-disorder transition temperature, the disordered states are locally well-segregated and form bicontinuous network phases. This study furnishes detailed insights into structure-property relationships for mesophase formation on the 1-nm length scale that will aid further miniaturization for numerous applications.