The carbon n.m.r. spectra of 29 substituted chromones have been measured and assigned. The data for these and 10 other chromone derivatives show that the chemical shifts of the six benzenoid carbon nuclei are affected to a relatively small extent (<±2 p.p.m.) by changes in the substituents on the pyrone ring. Similarly the pyrone ring carbons (C-2, C-3, and C-4) are relatively insensitive to changes
已测量并确定了29个取代的
色酮的碳nmr光谱。这些和其他10个
色酮衍
生物的数据表明,六个苯环碳核的
化学位移受
吡喃酮环上取代基的变化影响较小(<±2 ppm)。类似地,吡喃环碳(C-2,C-3和C-4)对苯环的C-6和C-7处的取代基的变化相对不敏感。碳核磁共振数据可用于鉴定异构色原酮衍
生物,否则很难区分。