PATENT CLAIM ANALYSIS

Application Number: 16083128
Application Type: Utility
Filing Date: 2018-09
Publication Date: 2019-04
Patent Classification: ["544", "277000"]

Abstract:
The invention provides a new convergent approach for the synthesis of 2′-fluoro-6′- methylene-carbocyclic adenosine (FMCA) and 2′-fluoro-6′-methylene-carbocyclic guanosine (FMCG) from a readily available starting material in eight steps. An efficient and practical methodology for stereospecific preparation of a versatile carbocyclic key intermediate, (1S,3R,4R)-3-tert-butoxy-4-(tert-butoxymethyl)-2-fluoro-5-methylenecyclopentanol (compound 8 of scheme 1A or a) in only six (6) steps is also provided. Prodrugs of these compounds are also prepared.

Claim (Index 2):
A process to synthesizing compound 8: from substituted pentanone derivative 1: Comprising reacting compound 1 with paraformaldehyde in the presence of diisopropyl ammonium trifluoroacetate salt and diisopropylamine in solvent to produce compound 2A followed by stereoselectively reducing the keto group of compound 2A using sodium borohydride in the presence of a Lewis acid in solvent at reduced temperature to produce compound 2; Reacting compound 2 with AlMe 3  in solvent to produce compound 3 Reacting compound 3 with tert-butyldiphenylsilyl chloride in weak base to produce compound 4; Fluorinating compound 4 with diethylaminosulfur trifluoride (DAST) to stereoselectively fluorinate the 2\u2032 position of compound 4 to produce compound 7 which is then deprotected to remove the silyl protecting group to provide, compound 8 wherein the synthesis of compound 8 may be conducted in a single pot or in steps, with optional separation and/or purification of any one or more steps to produce compounds 2A, 2, 3, 4, 7 and/or 8.

Metadata:
- Claim Count in Document: 15.0
- Percentile: 97.0
- Lexical Diversity: 1.37705
- Patent Class: 544.0
- Transitional Phrase Type: none
- Component Type: 0
- Foreign Priority: False
- Related Applications: ['14631209', '15287805', '15609080', '14079412', '13107713']

Analysis Scores:
- 35 USC 101 Eligibility (BERT): 0.7288557711637044
- 35 USC 102 Novelty (BERT): 0.524730573829787
- Combined Prediction Score: 0.7084432514303126
- Mean Citation Score: 235.178488
- Max Citation Score: 306.3729600000001
- Similarity Product: 204.6438743522073

Labels:
- Claim Label 101: 1
- Claim Label 102: 1
- Claim Label 103: 1
- Claim Label 112: 1
- Combined Label: 1
- Label 101 Adjusted: 1

Dataset: test