XVI CONTENTS 



V. Chemistry of the Phosphatides and CerebrosideS (continued) 



(1) Structure of the Plasmalogens 471 



(2) Properties of the Plasmalogens 472 



(3) Hydrolysis of the Plasmalogens 472 



B. Cerebrosides 473 



1 . Introduction 473 



2 . Structure of the Cerebrosides 475 



3 . Preparation of the Cerebrosides 477 



( 1 ) Thierfelder Method for the Preparation of Phrenosine 477 



(2) Preparation of Phrenosine and Cerasine by the Rosen eim 



Method 478 



a. Separation of Crude Cerebrosides 478 



b. Removal of Phosphorus-Containing Impurities 478 



c. Separation of Phrenosine and Cerasine 478 



d. Purification of Phrenosine 479 



e. Purification of Cerasine 479 



(3) Loening and Thierfelder Method for Removing Phosphatides 



by Use of Barium Hydroxide 480 



(4) Preparation of Nervone According to Method of Klenk 480 



a. Separation of Crude Nervone 480 



b. Purification of Nervone 481 



(a) First Method of Fractional Crystallization 481 



(b) Second Method of Purification 482 



(c) Purification as the Acetyl Compound 482 



4. Tests for Purity of the Cerebrosides 482 



(1) Proof of the Absence of Phosphatides 482 



(2) Crystallization Test 482 



(3) Seienite Plate Test 482 



5 . Properties of the Cerebrosides 484 



( 1 ) Phrenosine 484 



(2) Cerasine 486 



(3) Nervone 487 



6 . Hydrolysis of the Cerebrosides 487 



7. Chemistry and Properties of Hydrolysis Products of the Cerebrosides 488 



( 1 ) Psychosine 488 



a. Structure of Psychosine 489 



b. Preparation of Psychosine 490 



c. Properties of Psychosine 490 



(2) The Ceramides 491 



a. Structure of Cerebronyl-A'-Sphingosine 491 



b. Preparation of Cerebronyl-A'-Sphingosine 492 



c. Properties of Cerebronyl-A'-Sphingosine 492 



(3) Sphingosine 493 



(4) Fatty Acids 493 



a. Cerebronic Acid 493 



(a) Structure 493 



(b) Properties 494 



b. Lignoceric Acid 495 



(a) Structure 495 



(b) Properties 496 



c. Nervonic Acid 496 



