Abstract: A method of purifying 1&agr;,24(S)-dihydroxyvitamin D2 to obtain 1&agr;,24(S)-dihydroxyvitamin D2 in crystalline form. The method includes the steps of boiling a solvent under inert atmosphere, dissolving a product containing 1&agr;,24(S)-dihydroxyvitamin D2 to be purified in the solvent, cooling the solvent and dissolved product below ambient temperature for a sufficient amount of time to form a precipitate of 1&agr;,24(S)-dihydroxyvitamin D2 crystals, and recovering the 1&agr;,24(S)-dihydroxyvitamin D2 crystals. The purification technique involves using one of several binary solvent systems, namely, acetone and hexane, 2-propanol and hexane, or ethyl formate and petroleum ether.

Abstract: A method of modifying or altering the structure of a 1&agr;-hydroxylated vitamin D compound to increase its biological activity by altering the conformational equilibrium of the A-ring to favor a chair conformation that presents the 1&agr;-hydroxyl in the axial orientation. This is accomplished by either locking the A-ring chair conformation in a geometry having an axially orientated 1&agr;-hydroxyl, or by the addition of one or more substituents to the A-ring which interact with other substituents in the molecule or on the A-ring to provide a driving force to the A-ring to adopt a chair conformation which presents the 1&agr;-hydroxyl in the axial orientation.

Abstract: A method of purifying 1&agr;,24(S)-dihydroxyvitamin D2 to obtain 1&agr;,24(S)-dihydroxyvitamin D2 in crystalline form. The method includes the steps of boiling a solvent under inert atmosphere, dissolving a product containing 1&agr;,24(S)-dihydroxyvitamin D2 to be purified in the solvent, cooling the solvent and dissolved product below ambient temperature for a sufficient amount of time to form a precipitate of 1&agr;,24(S)-dihydroxyvitamin D2 crystals, and recovering the 1&agr;,24(S)-dihydroxyvitamin D2 crystals. The purification technique involves using one of several binary solvent systems, namely, acetone and hexane, 2-propanol and hexane, or ethyl formate and petroleum ether.

Abstract: This invention provides a novel class of vitamin D related compounds, namely, 2-alkyl-19-nor-vitamin D derivatives, as well as a general method for their chemical synthesis. The compounds have the formula: where Y1 and Y2, which may be the same or different, are each selected from the group consisting of hydrogen and a hydroxy-protecting group, R6 is selected from the group consisting of alkyl, hydroxyalkyl and fluoroalkyl, and where the group R represents any of the typical side chains known for vitamin D type compounds. These 2-substituted compounds, especially the 2&agr;-methyl and the 2&agr;-methyl-20S derivatives, are characterized by relatively high intestinal calcium transport activity and relatively high bone calcium mobilization activity resulting in novel therapeutic agents for the treatment of diseases where bone formation is desired, particularly low bone turnover osteoporosis.

Abstract: A method of purifying 1&agr;-hydroxyvitamin D2 to obtain 1&agr;-hydroxyvitamin D2 in crystalline form. The method includes the steps of boiling a solvent selected from the group consisting of ethyl formate, ethyl acetate and a 2-propanol-hexane mixture under inert atmosphere, dissolving a product containing 1&agr;-hydroxyvitamin D2 to be purified in the solvent, cooling the solvent and dissolved product below ambient temperature for a sufficient amount of time to form a precipitate of 1&agr;-hydroxyvitamin D2 crystals, and recovering the 1&agr;-hydroxyvitamin D2 crystals. Petroleum ether is also added to the solvent after dissolving the product to be purified in the solvent.

Abstract: A method of modifying or altering the structure of a 1&agr;-hydroxylated vitamin D compound to increase its biological activity by altering the conformational equilibrium of the A-ring to favor a chair conformation that presents the 1&agr;-hydroxyl in the axial orientation. This is accomplished by either locking the A-ring chair conformation in a geometry having an axially orientated 1&agr;-hydroxyl, or by the addition of one or more substituents to the A-ring which interact with other substituents in the molecule or on the A-ring to provide a driving force to the A-ring to adopt a chair conformation which presents the 1&agr;-hydroxyl in the axial orientation.

Abstract: This invention provides a novel class of vitamin D related compounds, namely, the 2-alkyl-19-nor-vitamin D derivatives, as well as a general method for their chemical synthesis. The compounds have the formula: where Y1 and Y2, which may be the same or different, are each selected from the group consisting of hydrogen and a hydroxy-protecting group, R6 is selected from the group consisting of alkyl, hydroxyalkyl and fluoroalkyl, and where the group R represents any of the typical side chains known for vitamin D type compounds. These 2-substituted compounds, especially the 2&agr;-methyl and the 2&agr;-methyl-20S derivatives, are characterized by relatively low intestinal calcium transport activity and high bone calcium mobilization activity resulting in novel therapeutic agents for the treatment of diseases where bone formation is desired, particularly low bone turnover osteoporosis.

Abstract: This invention provides a novel class of vitamin D related compounds, namely, the 2-alkyl-19-nor-vitamin D derivatives, as well as a general method for their chemical synthesis. The compounds have the formula: ##STR1## where Y.sub.1 and Y.sub.2, which may be the same or different, are each selected from the group consisting of hydrogen and a hydroxy-protecting group, R.sub.6 is selected from the group consisting of alkyl, hydroxyalkyl and fluoroalkyl, and where the group R represents any of the typical side chains known for vitamin D type compounds. These 2-substituted compounds, especially the 2.alpha.-methyl and the 2.alpha.-methyl-20S derivatives, are characterized by relatively low intestinal calcium transport activity and high bone calcium mobilization activity resulting in novel therapeutic agents for the treatment of diseases where bone formation is desired, particularly low bone turnover osteoporosis.

Abstract: A method of modifying or altering the structure of a 1.alpha.-hydroxylated vitamin D compound to increase its biological activity by altering the conformational equilibrium of the A-ring to favor a chair conformation that presents the 1.alpha.-hydroxyl in the axial orientation. This is accomplished by either locking the A-ring chair conformation in a geometry having an axially orientated 1.alpha.-hydroxyl, or by the addition of one or more substituents to the A-ring which interact with other substituents in the molecule or on the A-ring to provide a driving force to the A-ring to adopt a chair conformation which presents the 1.alpha.-hydroxyl in the axial orientation.

Abstract: This invention provides a novel class of vitamin D related compounds, namely, the 2-alkylidene-19-nor-vitamin D derivatives, as well as a general method for their chemical synthesis. The compounds have the formula: ##STR1## where Y.sub.1 and Y.sub.2, which may be the same or different, are each selected from the group consisting of hydrogen and a hydroxy-protecting group, R.sub.6 and R.sub.8, which may be the same or different, are each selected from hydrogen, alkyl, hydroxyalkyl and fluoroalkyl, or when taken together represent the group --(CH.sub.2).sub.x -- where x is an integer from 2 to 5, and where the group R represents any of the typical side chains known for vitamin D type compounds. These 2-substituted compounds are characterized by low intestinal calcium transport activity and high bone calcium mobilization activity resulting in novel therapeutic agents for the treatment of diseases where bone formation is desired, particularly low bone turnover osteoporosis.

Abstract: In vitro incubation of all-trans-retinol (atROL) with kidney homogenate from vitamin A deficient and retinoic acid supplemented (VAD-RAS) female rats produced a new retinol metabolite. The metabolite has the structure ##STR1## and is believed useful for the treatment of skin disorders such as acne, psoriasis, and ultraviolet light skin damage, as well as for promoting female fertility and the maintenance of pregnancy.

Abstract: This invention provides a novel class of vitamin D-related compounds, namely the 1c-hydroxy-19-nor-vitamin D analogs, as well as a general method for their chemical synthesis. The compounds exhibit pronounced activity in arresting the proliferation of undifferentiated cells, including malignant cells, and in inducing their differentiation, and thus represent novel therapeutic agents for the treatment of malignant and other diseases characterized by the proliferative growth of undifferentiated cells. Formulations for therapeutic use and treatment methods are also provided.

Abstract: 18,19-dinor-vitamin D.sub.3 analogs in which the angular methyl group attached to carbon 13 of the CD-ring and the exocyclic methylene group attached to carbon 10 of the A-ring have been removed and replaced by a hydrogen atom. The 18,19-dinor vitamin D compounds are characterized by relatively high cell differentiation activity, and marked intestinal calcium transport activity while exhibiting lower activity than 1.alpha.,25-dihydroxyvitamin D.sub.3 in their ability to mobilize calcium from bone. These compounds would be useful for the treatment of diseases where bone formation is desired, such as osteoporosis, because of their preferential calcemic activity, and for the treatment of psoriasis due to their cell differentiation activity.

Abstract: 18-nor-vitamin D.sub.3 analogs in which the angular methyl group attached to carbon 13 of the CD-ring has been removed and replaced by a hydrogen atom. The 18-nor vitamin D compounds are characterized by relatively high cell differentiation activity, while exhibiting much lower activity than 1.alpha.,25-dihydroxyvitamin D.sub.3 in their ability to mobilize calcium from bone. These compounds would be useful for the treatment of diseases where bone formation is desired, such as osteoporosis, because of their preferential calcemic activity, and for the treatment of psoriasis due to their cell differentiation activity.

Abstract: 18,19-dinor-vitamin D.sub.3 analogs in which the angular methyl group attached to carbon 13 of the CD-ring and the exocyclic methylene group attached to carbon 10 of the A-ring have been removed and replaced by a hydrogen atom. The 18,19-dinor vitamin D compounds are characterized by relatively high cell differentiation activity, and marked intestinal calcium transport activity while exhibiting lower activity than 1.alpha.,25-dihydroxyvitamin D.sub.3 in their ability to mobilize calcium from bone. These compounds would be useful for the treatment of diseases where bone formation is desired, such as osteoporosis, because of their preferential calcemic activity, and for the treatment of psoriasis due to their cell differentiation activity.

Abstract: 18,19-dinor-vitamin D.sub.3 analogs in which the angular methyl group attached to carbon 13 of the CD-ring and the exocyclic methylene group attached to carbon 10 of the A-ring have been removed and replaced by a hydrogen atom. The 18,19-dinor vitamin D compounds are characterized by relatively high cell differentiation activity, and marked intestinal calcium transport activity while exhibiting lower activity than 1.alpha.,25-dihydroxyvitamin D.sub.3 in their ability to mobilize calcium from bone. These compounds would be useful for the treatment of diseases where bone formation is desired, such as osteoporosis, because of their preferential calcemic activity, and for the treatment of psoriasis due to their cell differentiation activity.

Abstract: 18-nor-vitamin D.sub.3 analogs in which the angular methyl group attached to carbon 13 of the CD-ring has been removed and replaced by a hydrogen atom. The 18-nor vitamin D compounds are characterized by relatively high cell differentiation activity, while exhibiting much lower activity than 1.alpha.,25-dihydroxyvitamin D.sub.3 in their ability to mobilize calcium from bone. These compounds would be useful for the treatment of diseases where bone formation is desired, such as osteoporosis, because of their preferential calcemic activity, and for the treatment of psoriasis due to their cell differentiation activity.

Abstract: This invention provides a novel class of vitamin D-related compounds, namely the 1.alpha.-hydroxy-19-nor-vitamin D analogs, as well as a general method for their chemical synthesis. The compounds exhibit pronounced activity in arresting the proliferation of undifferentiated cells, including malignant cells, and in inducing their differentiation, and thus represent novel therapeutic agents for the treatment of malignant and other diseases characterized by the proliferative growth of undifferentiated cells. Formulations for therapeutic use and treatment methods are also provided.

Abstract: 18-nor-vitamin D.sub.3 analogs in which the angular methyl group attached to carbon 13 of the CD-ring has been removed and replaced by a hydrogen atom. The 18-nor vitamin D compounds are characterized by relatively high cell differentiation activity, while exhibiting much lower activity than 1.alpha.,25-dihydroxyvitamin D.sub.3 in their ability to mobilize calcium from bone. These compounds would be useful for the treatment of diseases where bone formation is desired, such as osteoporosis, because of their preferential calcemic activity, and for the treatment of psoriasis due to their cell differentiation activity.

Abstract: This invention provides a novel class of vitamin D-related compounds, namely the 1.alpha.-hydroxy-19-nor-vitamin D analogs, as well as a general method for their chemical synthesis. The compounds exhibit pronounced activity in arresting the proliferation of undifferentiated cells, including malignant cells, and in inducing their differentiation, and thus represent novel therapeutic agents for the treatment of malignant and other diseases characterized by the proliferative growth of undifferentiated cells. Formulations for therapeutic use and treatment methods are also provided.