A linear mathematical relationship hidden in the Woodward UV rules for α,β-unsaturated ketones

A linear mathematical relationship, λcal = 211 + 12Nsub + 5Nexo, hidden in the classic Woodward UV rules was discovered by solving a linear equation in three variables based on the original descriptive Woodward UV rules. This linear equation is accurate for the calculation of the UV maximum absorption wavelengths (λmax) of various α,β-unsaturated ketones in the Woodward UV rules, which should inspire new understanding and facilitate studying of this important work.