DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Application Status
The amendment filed on 5/12/2026 in response to the Non-Final Office action of 2/12/2026 is acknowledged and has been entered. Claims 1, 4 and 6 are currently pending and under consideration.
Response to Amendment
The declaration under 37 CFR 1.132 filed on 05/12/2026 is insufficient to overcome the rejections set forth in the last Office action for the following reasons:
The declaration provides evidence in an attempt to establish the high purity of the final
product obtained by the claimed method (HPLC 99.809%, a single DSC peak is indicative of the absence of impurities, both shown in Figure 1 and Figure 2) is unique in the field enhancing its practical applicability (See figures 1 and 2 of the declaration).
The evidence has been carefully considered, but is not found persuasive.
While the examiner acknowledges Figures 1 and 2 and the declarants assertion that the product is quantitatively pure, the declarant has not provided any comparative data to show that MTX-1 obtained, for example, by the method of the prior art will result in a purity that is substantially or unexpectedly different. Moreover, the claims encompass two starting materials the “nitrate” or the “bicarbonate” and it is unclear which starting material was used since the specification appears to provide two examples each of which use the nitrate. This appears to be important since each of the starting materials gives different needle sizes, yields and purity. For example, Fronabarger et al. (cited in the prior office action) teach that although aminoguanidine is a more costly starting material, it gave small needles of MTX-1 vs. aminoguanidine bicarbonate which is more cost effective and produces MTX-1 in higher yield and better quality (page 37, 2. Materials and Methods). As such, the declaration is insufficient to overcome the rejections set forth in the last Office action.
Rejections Maintained, but amended in view of Applicants amendments:
Note: Upon review of the prior Non-Final office action, the Examiner discovered that claims 4 and 7 were accidentally omitted in the 2nd 103 rejection on page 8 of the office action. This appears to be a clerical error since the 2nd 103 rejection was specifically made to address that the combination of Fronabarger and Williams, Patinkin et al. and Anderson did not teach a one-pot synthesis without purification. Applicants addressed the teachings of Hayashi in their response. As such, it is the examiner opinion that Applicants recognized the oversight.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 1, 4 and 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Fronabarger and Williams (US8524019B2, 2013-11-03) in view of Patinkin et al. (J. Am. Chem. Soc. 1955; 77(3), 562-567), Anderson, Neal (Practical Process Research and Development, San Diego, Academic Press, 2000) and Hayashi, Yujiro (Chem. Sci. 2016; 7: 866).
Fronabarger and Williams teach that Tetrazene is widely used in ordinance systems as a sensitizer of primer mixes for use in both percussion and stab applications (column 1, lines 28-31). However, Fronabarger and Williams teach that Tetrazene suffers from a number of issues, most importantly low thermal and hydrolytic stabilities, wherein it has been demonstrated that Tetrazene readily decomposes at approximately 90C which is the temperature range that may be encountered during storage and some parts of the world (Column 2, lines 24-29). Accordingly, Fronabarger and Williams teach a possible alternative to Tetrazene referred to as MTX-1 which is conveniently prepared from Tetrazene in one step from an aqueous solution (Column 3, lines 63-67). Regarding tetrazene, Fronabarger and Williams teach that tetrazene is easily produced from either aminoguanidine nitrate or aminoguanidine bicarbonate (page 37, 2, Materials and Methods). For example, Fronabarger and Williams teach MTX-1 was prepared by suspending Tetrazene in HNO3 (Nitric acid) and adding NaNO2 (Sodium Nitrite) dissolved in 30mL of water to the suspension at room temperature, stirring the reaction for 4.5 hrs, filtering the white suspension, washing the white suspension with water and drying in a convection over at 60oC.
Fronabarger and Williams does not specifically teach how tetrazene was produced or that the reaction occurs as a one-pot synthesis which does not require purification of the Tetrazene. Moreover, Fronabarger and Williams do not teach that MTX-1 was washed with water and isopropyl alcohol.
Patinkin et al. teach the reinvestigation of the structure of the primary explosive Tetracene (Abstract). Specifically, Patinkin et al. teach a method of making Tetracene comprising mixing aminoguanidinium nitrate in water with sodium nitrite at room temperate and reacting the mixture for 40 hrs until a solid had formed, washing with water, ethanol and water (page 566, 1st column, 1st full paragraph of Experimental).
Hayashi teaches that the one-pot synthesis of a target molecule in the same reaction vessel is widely considered to be an efficient approach in synthetic organic chemistry because several synthetic transformations and bond forming steps can be carried out in a single pot which circumvents several purification procedures at the same time (Abstract and p 866 2nd column, paragraph bridging 1st column). Thus, Hayashi teaches that one-pot synthesis can thus minimize chemical waste, save time and simplify practical aspects (p 866 2nd column, paragraph bridging 1st column).
Anderson teaches that there are two purposes in applying a wash to a product wet cake. (page 241). The most common is to displace impurities adsorbed as mother liquor to the surfaces of solids (page 241). The second reason for applying a wash to a wet cake is to displace the solvent with another solvent, usually a lower-boiling solvent to ease drying of the product. In this case it is essential that the solvent applied dissolve as little product as possible and temperature selection may be important (page 241). Anderson teaches guidelines for washing a product in Table 11.6. Anderson further provides a listing of common solvents such as ethanol and isopropyl alcohol and their respective boiling point 78oC and 81oC respectively (page 86, Table 4.3).
It would have been prima facie obvious to one of ordinary skill in the art, prior to the effective filing date of the instantly claimed invention, to modify the method taught by Fronabarger and Williams to prepare Tetrazene by the method taught by Patinkin et al.. One of ordinary skill in the art would have been motivated to make such a modification, with a reasonable expectation of success, because:
- Fronabarger and Williams teaches that one of the disadvantages of Tetrazene is decomposition, specifically decomposition at storage temperatures. For example, Fronabarger and Williams teach that the decomposition of Tetrazene is complete after 1 week at 90oC and appears to be auto-catalytic (column 2, lines 53-55).
Moreover, it would have been prima facie obvious to one of ordinary skill in the art, prior to the effective filing date of the instantly claimed invention, to modify the method taught by the combination of Fronabarger and Williams and Patinkin et al. to a one-pot synthesis in view of the teachings of Hayashi. One of ordinary skill in the art would have been motivated to make such a modification, with a reasonable expectation of success, because:
-Hayashi recognizes the efficiencies that can be gained by performing a series of steps in one-pot,
- Fronabarger and Williams teach the disadvantages of Tetrazene (the intermediate) include temperature stability, as well as, hydrolytic decomposition (column 2, lines 53-63); and further
-Both Fronabarger and Williams and Patinkin et al. chemical reactions formed in the same solvent system (water) and both utilize sodium nitrite.
Lastly, it would have been prima facie obvious to one of ordinary skill in the art, prior to the effective filing date of the instantly claimed invention, to modify the method to include isopropyl alcohol in addition to water in the wash step in view of the teachings of Anderson. One of ordinary skill in the art would have been motivated to make such a modification, with a reasonable expectation of success, because:
- Anderson teaches that the second reason for applying a wash to a wet cake is to displace the solvent with another solvent, usually a lower-boiling solvent to ease drying of the product. In this case it is essential that the solvent applied dissolve as little product as possible and temperature selection may be important
While the rejection has been amended in view of Applicants amendments, the examiner would like to address Applicants arguments as they relate to the present rejection.
In response to the previous rejections, Applicants contend that Patinkin teaches the formation of tetrazene from the interaction of aminoguanidine and sodium nitrite in the absence of an acid. As such, Applicants contend that the starting material, aminoguanidine, as suggested by Patinkin, is different from the starting materials aminoguanidine nitrate or aminoguanidine bicarbonate as disclosed by the proposed method. In particular, Applicants assert that by using aminoguanidine nitrate or aminoguanidine bicarbonate, NOT aminoguanidine, MTX-1 is prepared safely and on industrial scale with quantitative purity. Applicants further contend that the one step process disclosed in the currently amended independent claim avoids the step of making tetrazene, isolating and purifying it, thereby improving the efficiency and scalability of the method, wherein the method incorporates reaction conditions that create the required conjugated double bonds in the molecules backbone. Regarding Anderson and Hayashi, Applicants assert that neither teach the method of synthesis of MTX as disclosed in the present disclosure.
These arguments are carefully considered, but are not found persuasive.
Regarding Applicants argument pertaining to the Patinkin teachings, the Examiner is confused by Applicants contention that Patinkin teaches a different starting material, e.g. aminoguanidine, versus the claimed aminoguanidine nitrate. While the Examiner acknowledges that Patinkin refers to the starting material as aminoguanidinium nitrate, the Examiner recognizes that this is the same compound as the claimed aminoguanidine nitrate. Moreover, the first step of the instantly claimed process appears to be identical to the method taught by Patinkin. In view of this, while the Examiner agrees with Applicants contention that the step of isolating and purifying tetrazene does not occur in the instantly claimed method, the Examiner is perplexed by Applicants contention that tetrazene is not produced in the first step. Applicants are reminded that the test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981). As discussed above, both the synthesis of MTX-1 and tetrazene are known in the art, wherein MTX-1 is made using tetrazene as the starting material. However, as noted in the prior art and acknowledged by Applicants, tetrazene suffers from a number of issues such as being both thermally and hydrolytically unstable. As such, it view of the teachings of Hayashi, it would be prima facia obvious to combine the two steps into a one-pot synthesis. For these reasons, the arguments are not found persuasive.
Conclusion
Therefore, No claim is allowed.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to BRANDON J FETTEROLF whose telephone number is (571)272-2919. The examiner can normally be reached M-F 6AM-4PM.
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BRANDON J. FETTEROLF, PHD
Primary Patent Examiner
Art Unit 1626
/BRANDON J FETTEROLF/Primary Examiner, Art Unit 1626
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