2C-G is a psychedelic phenethylamine of the 2C family. First synthesized by Alexander Shulgin, it is sometimes used as an entheogen. It has structural and pharmacodynamic properties similar to 2C-D and Ganesha. Like many of the phenethylamines in PiHKAL (Phenethylamines i Have Known And Loved), 2C-G and its homologues (see below) have only been taken by Shulgin and a small test group, making it difficult to ensure completeness when describing effects.

2C-G is 3,4-dimethyl-2,5-dimethoxyphenethylamine, with the formula C₁₂H₁₉NO₂. There are 209.284 grams of C₁₂H₁₉NO₂ per mole.

In Shulgin's book PiHKAL, the dosage range is listed as 20 to 35 mg. Effects are similar to the related Ganesha, and are extremely long lasting; the duration is 18–30 hours. Visual effects are muted or absent, and it is described in PiHKAL as an "insight-enhancer". Unlike other members of the 2C family, 2C-G is nearly as potent as its amphetamine cousin.

Several homologues of 2C-G were also synthesized by Shulgin. These include 2C-G-3, 2C-G-5, and 2C-G-N. Some, such as 2C-G-2 and 2C-G-4, are possible to synthesize in principle but impossible or extraordinarily difficult to do so in practice.