Doxercalciferol → Isoergosterone

HRID 845356

反応式

HRID 845356 の反応式
C[C@@H]([C@@H]1[C@@]2(C)CCC/C(=C\C=C3\C[C@@H](O)C[C@H](O)C\3=C)/[C@@H]2CC1)/C=C/[C@@H](C(C)C)C.O1[C@H:33]2[C:34](=[O:60])[CH:35]=[C:36]3[C@:57]([CH3:58])([C@@H:32]12)[C@@H:56]1[C@H:39]([C@H:40]2[C@:53]([CH3:59])([CH2:54][CH2:55]1)[C@@H:43]([C@H:44]([CH3:52])[CH:45]=[CH:46][C@H:47]([CH3:51])[CH:48]([CH3:50])[CH3:49])[CH2:42][CH2:41]2)[CH:38]=[CH:37]3>>[CH3:52][C@@H:44]([C@@H:43]1[C:53]2([CH3:59])[CH2:54][CH2:55][CH:56]3[C:57]4([CH3:58])[C:36](=[CH:35][C:34]([CH2:33][CH2:32]4)=[O:60])[CH:37]=[CH:38][CH:39]3[CH:40]2[CH2:41][CH2:42]1)/[CH:45]=[CH:46]/[C@@H:47]([CH:48]([CH3:49])[CH3:50])[CH3:51]

参加物

3

反応物 2

HCID 5281107DoxercalciferolHCID 539642531alpha,2alpha-Epoxy-ergosta-4,6,22-trien-3-one

生成物 1

HCID 101667976Isoergosterone

実験手順

1α-Hydroxy vitamin D2 exhibiting strong vitamin D activity is disclosed in U.S. Pat. No. 3,907,843. A synthetic route to 1α-hydroxy vitamin D2 disclosed therein is shown in the following reaction scheme I, which includes conversion of isoergosterone (compound 1) prepared from ergosterol to ergosta-1,4,6,22-tetraen-3-one (compound 2) followed by reaction with hydrogen peroxide to give 1α,2α-epoxy-ergosta-4,6,22-trien-3-one (compound 3), reaction of this compound with liquid ammonia and metal lithium to give 1α-hydroxy-7,8-dihydroergosterol (compound 4) followed by acetylation to give 1α-acetoxy-7,8-dihydroergosteryl acetate (compound 5), dehydrogenation of this compound to 1α-hydroxyergosteryl diacetate (1α,3β-diacetoxy-ergosta-5,7,22-trien)(compound 6), irradiation of this compound with light, causing cleavage of the ring to give 1α,3β-diacetoxy previtamin D2 (compound 7) and thermal isomerization and deacetylation of this compound to give 1α-hydroxy vitamin D2 (compound 8). The synthesis of 1α-hydroxy vitamin D2 by the above processes, however, gives rise to a number of problems. The reaction yield of the compounds is low including 16% yield in the formation of compound 5 from compound 3 and less than 10% yield in the formation of compound 6 from compound 5, and hence the overall yield through the synthesis of compound 6 from compound 1 amounts to less than 0.4%. In the conversion of compound 3 into compound 4, use of liquid ammonia and metal lithium is highly dangerous. In the conversion of compound 5 into compound 6, there is formed as by-products an isomeric compound 9 (1α,3β-diacetoxy ergosta-4,6,22-trien) which is difficult to separate and is responsible for reducing the purity of 1α-hydroxy vitamin D2. In view of the foregoing problems, the prior processes are not satisfactory for the production of 1α-hydroxy vitamin D2 in industrial scale. ##STR1##

後処理

  1. customhowever, gives rise to a number of problems

出典と根拠

ORDレコード
ord-bd39375af662410eaa99b7e9ee879557
出典データセット
uspto-grants-1988_07
特許番号
US04758383

関連ノート

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