Long-acting contraceptive agents: Esters of norethisterone with α- and/or β-chain branching

Watson, T.G.; Hosking, Michael P.; Herz, Josef E.; Torres, J.V.; Müller, Joachim; Murillo, A. García; Cruz, Silvia L.; Shafiee, Abbas; Vossoghi, M.; Savabi, Fatemeh; Sotheeswaran, Subramaniam; Puvanesarajah, Velupillai

doi:10.1016/0039-128x(83)90096-x

Cited by 5 publications

(1 citation statement)

References 8 publications

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“…Thus, the commercially available steroid propargylic alcohol 11 (norethindrone) was converted to the corresponding propargylic isobutyrate ester 12a , quantitatively, employing standard conditions, i.e., isobutyric anhydride, pyridine, and a catalytic amount of DMAP. Treatment of this propargylic isobutyrate ester 12a with 5 mol % potassium tetrabromopalladate and 2 equiv of water in DME in an oxygen atmosphere at 65 °C resulted in the formation of unsaturated isobutyrate 13a in 85% yield.…”

Section: Resultsmentioning

confidence: 99%

An Efficient Route for the Preparation of a 21-Fluoro Progestin-16α,17α-Dioxolane, a High-Affinity Ligand for PET Imaging of the Progesterone Receptor

et al. 2002

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Two different synthetic routes were explored for the synthesis of fluoro furanyl norprogesterone (FFNP) 1, a high-affinity ligand for the progesterone receptor (PgR) that is being developed as a PET imaging agent for PgR-positive breast cancer. Both approaches proceed through a key intermediate, triol 5. The first approach, starting from keto-ketal 2, employed a dioxenyl group as a synthon for installing a corticosteroid side chain in keto-alcohol 4. The second approach, starting from propargylic acetate 12b, involved the application of a two-step method, a Pd(II)-catalyzed oxidative rearrangement followed by a base-catalyzed acetate rearrangement of the intermediate unsaturated acetate 13b, to generate the requisite corticosteroid side chain in keto-acetate 14b. This intermediate was further elaborated to the final product 1 via efficient dihydroxylation with potassium permangnate, furan acetalization with scandium triflate, and mesylation and fluorination reactions. The palladium-catalyzed route is considerably more efficient than the dioxene approach for the synthesis of key intermediate triol 5, and the scandium triflate-catalyzed acetalization, in particular, led to a considerable improvement in the overall yield of the endo furan acetal alcohol 16a. This route provides a major improvement in the overall yield of the final progestin target, FFNP 1.

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Section: Resultsmentioning

confidence: 99%

An Efficient Route for the Preparation of a 21-Fluoro Progestin-16α,17α-Dioxolane, a High-Affinity Ligand for PET Imaging of the Progesterone Receptor

et al. 2002

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QSAR of Steroids

Zeelen¹

1986

Quant. Struct.‐Act. Relat.

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Problems, specific for QSAR studies of steroids, are reviewed. The attention is drawn to the extensive use of X‐ray structure determinations to assist in weeding‐out chance correlations which arise from the need to use too small series of derivatives and the tendency in older studies to underestimate the flexibility of steroids. A series of papers on the QSAR of the cardiac glycosides illustrate some problems associated with the use of molecular modelling.

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