The present disclosure is concerned with 9-hydroxy-6-(pyrrolidin-2-yl)-3,4-dihydro-2H-pyrazino[ 1,2-c]pyrimidine- 1, 8-dione compounds for the treatment of various viral infections such as, for example, influenza virus. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present invention.
CLAIMS What is claimed is: 1. A compound having a structure represented by a formula: <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000158-0001" /> wherein: A is a 6-7 membered heterocycle; R<1>is C1-C3 alkyl, C1-C3 alkoxy, C1-C3 haloalkyl, C1-C3 alkylsulfonyl, or a 9- to 10- membered cycloaryl, wherein R<1>can further be independently substituted with one or more R<x>groups; R<x>is sulfonyl, oxo, C1-C2 haloalkyl, 5- to 6-membered aryl, or 5- to 6-membered heteroaryl, wherein R<x>can independently further be substituted with one or more R<a>groups; R<a>is C1-C2 alkyl, 5- to 6-membered aryl, 5- to 6-membered heteroaryl, or C1-C2 haloalkyl, wherein R<a>can independently be substituted with one or more R<al>groups; R<al>is halo, C1-C2 alkoxy, cyano, or C1-C2 haloalkyl; R<2>is C1-C2 alkyl, 5- to 6-membered aryl, oxo, 5- to 6-membered heteroaryl, or C1-C2 alkoxy, wherein R<2>can further be independently substituted with one or more R<y>groups; R<y>is halo, oxo, C1-C2 alkyl, sulfidyl, cyano, C1-C2 haloalkyl, or 5- to 6-membered aryl, wherein R<y>can independently further be substituted with one or more R<b>groups; R<b>is halo or 5- to 6-membered aryl; R<bl>is halo; and wherein the wavy line indicates either R or S enantiomer at that bond, or a pharmaceutically acceptable salt or hydrate thereof. 2. The compound of claim 1, wherein the compound has a structure represented by a formula: <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000159-0001" /> wherein: n is 1 or 2; R<1>is C1-C3 alkyl, C1-C3 haloalkyl, -(C1-C3 alkyl)OR<10>, -(C1-C3 alkyl)S0<2>R<10>, or Cy<1>; R<10>is C1-C2 alkyl or Ar<1>; Ar<1>is a 5- to 6-membered aryl or a 5- to 6-membered heteroaryl, and is substituted with 0, 1, 2, or 3 groups independently selected from halogen, - CN, C1-C2 alkyl, C1-C2 haloalkyl, and -C1-C2 alkoxy; Cy<1>is an unsubstituted 9- to 10-membered cycloalkyl group; R<2>is C1-C2 alkyl, -(C1-C2 alkyl)Ar<2>, -0(C1-C2 alkyl), -0(C1-C2 alkyl)Ar<2>, -(C1-C2 alkyl)OAr<2>, -S(C1-C2 alkyl), -S(C1-C2 alkyl)Ar<2>, -(C1-C2 alkyl)SAr<2>, or Ar<2>; and Ar<2>is a 5- to 6-membered aryl or a 5- to 6-membered heteroaryl, and is substituted with 0, 1, 2, or 3 groups independently selected from halogen, -CN, Cl- C2 alkyl, and C1-C2 haloalkyl, or a pharmaceutically acceptable salt thereof. 3. The compound of claim 2, wherein n is 1. 4. The compound of claim 2, wherein n is 2. 5. The compound of claim 2, wherein R<1>is a structure selected from: <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000160-0001" /> 6 The compound of claim 2, wherein R<2>is a structure selected from: <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000160-0002" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000161-0001" /> 7. The compound of claim 2, wherein the compound has a structure represented by a formula: <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000161-0002" /> 8. The compound of claim 2, wherein the compound has a structure represented by a formula: <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000161-0003" /> 9. The compound of claim 8, wherein R<10>is a structure selected from: <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000161-0004" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000162-0001" /> 10. The compound of claim 8, wherein R<2>is a structure selected from: <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000162-0002" /> 11. The compound of claim 2, wherein the compound has a structure: <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000162-0003" /> wherein: Q is O or SO2. 12. The compound of claim 11, wherein the compound has a structure: <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000163-0001" /> wherein: each of R<lla>, R<llb>, R<llc>, R<lld>, and R<lle>is independently selected from hydrogen, halogen, -CN, C1-C2 alkyl, C1-C2 haloalkyl, and -C1-C2 alkoxy, provided that at least two of R<lla>, R<iib>, R<iic>, Rn<d>, and R<iie>are hydrogen. 13. The compound of claim 2, wherein the compound is selected from: <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000164-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000165-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000166-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000167-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000168-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000169-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000170-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000171-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000172-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000173-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000174-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000175-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000176-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000177-0001" /> <img class="EMIRef" id="79065ddd-db7c-49d6-9347-9ec7eb64ebab-imgf000178-0001" /> 14. A pharmaceutical composition comprising a therapeutically effective amount of the compound of claim 1, and a pharmaceutically acceptable carrier. 15. A method of treating a viral infection in a subject in need thereof, the method comprising administering to the subject an effective amount of the compound of claim 1. 16. The method of claim 13, wherein the subject is a mammal. 17. The method of claim 14, wherein the mammal is a human. 18. The method of claim 13, wherein the effective amount is a therapeutically effective amount. 19. The method of claim 13, wherein the viral infection is influenza. 20. A kit comprising the compound of claim 1, and one or more of: (a) an antiviral agent; (b) an immunity booster; (c) instructions for administering the compound in connection with treating a viral infection; (d) instructions for administering the compound in connection with reducing the risk of viral infection; and (e) instructions for treating a viral infection.