ORCIN. 307 



Diacetylresorcin, C 6 H 4 (O.C 2 H 3 0) 2 , is produced by 

 the action of acetyl chloride on resorcin. Colorless 

 liquid, insoluble in water. 



Trinitroresorcin (Oxypicric acid, Styphnic acid), 

 C 6 H(^"0 2 ) 3 (OH) 2 . Is produced by the action of nitric 

 acid on morintannic acid, a number of gum-resins, 

 (galbanum, sagapenum, ammonia-gum), ancf a number 

 of vegetable extracts (of sapon-wood, Brazil-wood, etc.) 

 Is obtained from orcin by the action of nitric acid at 

 a low temperature. Pale yellow prisms or lamellae; 

 sublimable when carefully heated; difficultly soluble 

 in water; fusing point, 175.5. Strong, bibasic acid ; 

 yields salts that crystallize well and explode violently 

 when heated. 



Thiores orcin, C 6 H 4 (SH) 2 . Is produced when para- 

 disulphobenzolchloride (p. 270) is heated gently with 

 tin and hydrochloric acid. Crystalline mass, easily 

 volatile with water- vapor; fusing point, 27; boiling 

 point, 243. 



TJmbelliferone, C 6 H 4 2 (or C 9 H 6 3 ). Isomeric with 

 quinone. Is produced in the destructive distillation of 

 a number of resins, chiefly of umbelliferous plants, as 

 galbanura. Colorless, rhombic prisms, sparingly solu- 

 ble in cold water, easily soluble in alcohol, and ether. 

 The aqueous solution exhibits, by reflected light, 

 a splendid blue color. Melts at 240 ; sublimes with- 

 out decomposition. Yields resorcin when fused with 

 caustic potassa. 



2. Orcin. 



P7TT8O2 P<5TT3 j ^H 3 



L 1 (OH) 2 . 



It appears to be ready formed in a number of lichens. 

 Is formed from orsellic acid and other acids (lecanoric, 

 evernic, erythric acids) that occur in various lichens, 

 and bear a close relation to orsellic acid, either by 

 heating them alone, or by boiling them with strong 

 bases. It is further produced when aloes is melted 



