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Hydroxy groups of sugar can be converted to methyl ethers by treating with methyl iodide (CH₃I) and silver oxide (Ag₂O). CH₃-I group can be polarised by silver oxide (Ag₂O), which makes the methyl carbon more strongly electrophilic. Attack by the -OH group of carbohydrate is then followed by deprotonation which gives the ether.

Pyranose is a six-membered cyclic hemiacetal while a furanose is a five-membered cyclic hemiacetal.

1. α-¶Ù-´Ú°ù³Ü³¦³Ù´Ç´Ú³Ü°ù²¹²Ô´Ç²õ±ð on treatment with excess methyl iodide and silver oxide gives methyl 2,3,4,6, -tetra-O-methyl-α-D-fructofuranoside as the product.
   
2. β-¶Ù-²µ²¹±ô²¹³¦³Ù´Ç±è²â°ù²¹²Ô´Ç²õ±ð on treatment with excess methyl iodide and silver oxide gives methyl 2,3,4,6,-tetra-O-methyl-β-D-galactopyranoside as the product.